Must do list in Orlando

Here is a great website for all things Disney

http://allears.net/index.html

also, Disneyrunning.com has some great running maps for the orlando area

www.disboards.com

Go there and search.

Or ask a question, and I guarantee 10 answers within 1 minute.

It is one of the largest, most active forums on the web.

We went to Disney World last spring.  We went to each park for a day and then let the kids decide after that.  Their favorite - Epcot.

Call in advance and setup character dinners.  I saw someone already mentioned this.  In Epcot in the Viking country is a castle with the Disney princesses.

We had a great time at Gatorland. 

As for SeaWorld, unless they've changed the policy (w/ Budweiser being sold) - active military get in free.

I grew up in Orlando and my mom still live there.

For the Disney crowd:

Get a park hopper pass and do the typical disney things.  Start early and go to the farthest part of the park first and work your way back towards the entrance.  Most people always start at the front and go to the back.  Going far to near is more efficient and easier IMHO.  If you go to Epcot, eat at one of the country restaurants.  Country as in Italy, Spain, etc.  Try something new.  You can even do the around the world beer tour.  Highly recommended!  You get a beer in each "country". 

Outside Disney:

Downtown Disney is great!  I would recommend Cique Du Solei the resident show is La Nuba I believe.  Good stuff.  Down there you also have tons of restaurants and the Lego place which your kids will love.  I believe they also have a build a bear type place.

Non-Disney:

If you want real rollercoasters, then go to Islands of Adventure and the other theme parks down around I-drive.  I highly recommend them over the disney ones.  There is also Sea World if you're into water animals.

Random: 
I am pretty sure that Neport, RI does not have a Medival Times.  It is a GREAT time for both kids and parents as long as you don't mind getting your hands dirty.  Literally.  Think times when you ate with your hands.  Also for the shopping types, go to the Outlet Mall on Oakridge road.  That is the 'real' outlet.  They have a North Face, C9 and Pearl Zumi outlet for those triathlon clothing purchases!

If you want to do the character breakfast, I would call now.  They fill up fast.  They start booking 90 days out.  If you want to go to dinner with the Mrs, without the kids, I would recommend Victoria and Alberts in the Grand Floridian.  It's a pre-set 7 course meal.  One of the best meals I have ever had.  

 Another recommendation is to start each day as early as possible, go home in the afternoon and nap, then go back out at night for dinner and fireworks.  Those afternoon naps are great for kids and adults alike. 

If you are a baseball fan, I am sure that there are going to be some Spring Training games within an hour from you.  That might be fun for the kids and different from the amusement parks.  Cheaper too.

Have fun. 

If the weather is good the Disney water parks are a blast.  My kids (now 7 & 9) love Magic Kingdom. Other parks are good too as is Universal but a lot of the rides have height restrictions, last year or two mine became tall enough to open up their ride selections.

Downtown Disney or Universal City Walk are great places for adults to go out and have some "fun" at night.

Any family member or friend having a birthday while you're there?  Disney is having a free day promotion on your BD.  We're taking advantage of this in April.

Doesn't look like there are any favorable launches at Kennedy Space Center in March, only a late rocket (11pm) on the 5th.

My family has yearly passes to Disney, we go at least twice a year.  If you're going for a week, I'm going to assume 4 actual days at the "parks".

With those ages you can really do 2 days at Magic Kingdom.  I actually disagree with the Epcot thing.  Epcot is kinda' two parks in one, the front half and then the international expo section.  The front half there really isn't a ton to do for kids.  I think there are a total of maybe 4 rides for the younger kids.  If you decide to do Epcot, I'd make sure you have the "park hopper" option for your tickets.  This option lets you go from park-to-park-to-park in one day on one ticket.  So if you get bored with a park you can catch some Disney transport over to one of the other parks.

Animal Kingdom is fun, expecially if your kids are into animals.

I agree with doing a Character dinning, they are a blast, each park has their own.  We always do The Crystal Palace for breakfast or lunch.  You have to book these character dinnings early, they fill up fast.

Get fast passes for the popular rides.  You go to the ride you want to go on, put your park ticket through the machine and it spits out a special "fast pass" for that ride.  It lets you return at a later time and you get to go in a much shorter quicker "fast pass" line.

You have all girls?  Down Town Disney has the "bibity-bobity boutique"  Your little girls go in there and they get their hair done and get all decked out in their favorite Disney princesses costume.  Needs reservations and is a little pricey.  But it's a blast.  My daughter loved it.

If you don't want to do that, right inside of the Magic Kingdom, on main street, just as you enter, to the left in one of the buildings is a "barber shop"  you can go in there and they will do your kids hair, put ribbones and sparkles in it.

Also, I would check the Disney web page, see if during the time you are going they are having one of the night time special events, like the Pirate and Princess party.  These are great.  You pay an additional price, they close the park at 7pm and you get to come back when the park is closed for this pirate princess party.  All the big rides are open and the lines are wicked short.  (We rode thunder mountain 3 times in a row without having to get out of the cart!!!!)

Cinderallas castle is also a great dinning experience.  Try to schedule your meal for when the fire works are going off, you get a great view of the fireworks.

Also, here's a little seceret.  Near the Castle there is a little Rose garden, called Belle's Rose Garden.  About three times a night Belle comes out and reads stories to the kids.  She will pick like 4-5 kids to come up and play roles in the story telling.  Try to get there early, there's only I think 4 bench seats in the rose garden.  So seating is limited.  The closer to the stage the more likely your kids to get picked.

Also get a phot pass.  You will see photographers standing in front of the big attractions.  Ask for a photo pass.  It's free, they will take your picture say standing in front of the Castle or tower of Terror.  They scan your photo pass.   Then when you get home you go on line and you can look at all the photos they took and buy them.  They are a little pricey, but we always forget to bring a camera and I hate lugging around the video camera.

with your kids being young Epcot may not be a big hit with them.  In 2006 and 2007 we took our kids to Orlando for Christmas. My kids are now 7 & 9.  They were not very impressed with Epcot other than the fireworks...although I would have liked to spent more time there (But we were there for the kids).  They really like the Magic Kingdom and Animal Kingdom.  It was too cool for the waterparks so I can't tell you about that.  Universal is a lot of fun too but is not open as late as Disney and the kids preferred the Disney Parks.

Something else to keep in mind if you have a car is Kennedy Space Center.  It's maybe a 45-minute drive from Orlando and well at the time I didn't see the excitement with the kids like they had at the theme parks...my son is still talking about it over a year later.  Made a lasting impact on him!

Have a great time!

March is going to be a little crowded due to spring break so you want to get a plan if you're doing Disney.  You'll have to be there by opening (usually 9am, but may be earlier in March) if youw ant to get lots of rides in without long waits.  The lines get longer right around 11ish.

 I second the disboards.com. They will answer all of your questions and more. The main site that goes with that is wdwinfo.com - it's much easier to navigate than the actual Disney website.  They have all the calendars, event times, restaurant menus (huge help for us with picky kids), etc.

With three young girls you want to spend a lot fo time at Magic Kingdom.  There is now a Bibbity Bobbity Boutique inside the castle if they like to get all done up with fancy hair/dresses.  My kids have never wanted to do that (I'm glad - because it's expensive!), but we see tons of girls walking around alldolled up.

The princess castle meals and even the Norway princess meals may be booked by now.  If you can't get in there go to Crytal Palace for the meal with Pooh and friends - my kids loved that one and I liked the breakfast food.

Or, if you want to save money, you can bring your own food into the park and eat there.  We have a quiet little spot to the side of the castle where we like to eat our own picnic - this time we brought PB&J's, pretzels, chocolate milk & cookies - my kids loved it! 

Oh - and even though it is very expensive - I always recommend renting a stroller - even for your oldest DD.  There is so much walking there the young ones usually need to rest their feet at some point.  It's so much better than having them get fussy and fight - trust me- we've had at least two times where we skipped the stroller for the two oldest kids and halfway through the day we went back up to get one!  Most of my friends have told me this was the best advice I gave them.   If you have to rent a double it is $35 a day - pricey but worth every penny to skip the whining!

We go at least once a year and were there last weekend, if you have any questions just let me know. 

Like meat?

Go here:  http://www.texasdebrazil.com/

Don't each lunch that day however.

Bonus.. it's right across the street from the Bass Pro Shop..

Neverknew about this.  Looks like fun.  Have you done it?

http://www.universalorlando.com/citywalk.html

http://www.emerils.com/

City walk is a great place to go.  There is a lot of stuff for the kids and if you like GOOD food check out Emeril's restaurant.  Try to get a seat at the food bar if possible.  YOu can watch the cheifs prepare the meals and get free samples.  Great place.   Enjoy and keep us posted.

Edited to add web site.

I was there this past Friday with NO LINES on Hulk.   Great coaster and I got to ride it back to back to back.  It was awesome! A couple friends of mine and I went to Universal on Friday and the longest we had to wait for ANY ride was 10 minutes.  

The two younger kids of the OP will probably not enjoy Universal.  I have two 5yos and wouldn't take them at that age.  They wouldn't be able to ride most of the rides due to height and a lot of the rides produce an "intense" reaction which can be scary for younger ones. 

As for Disney, we were there in August.  My kids only enjoyed the Nemo ride and were to small to ride the others and got bored quickly in the world showcase so we spent little time there even though it would be one of my favs right now.  We really enjoyed Magic Kingdom and Hollywood Studios.  We also enjoyed Wild Kingdom but you can accomplish that park in one afternoon.