First Women-Specific Road Bike - Aluminum or Carbon? Double or Triple?

Hi everyone, and thank you for all the great information I am finding on this site, and in these forums!

I just did my first sprint tri, and loved it.  I currently ride a Kona Dr. Dew (kind of a hybrid commuter w/ disc brakes and flat bars) which is fine for the few races a year that I do, however, current bike is a bit oversized, and handling is impacted, therefore, I think I would like to upgrade to a quality road bike for regular riding and triathlons, and outfit my Kona for just the offroad trails I do on occaision, and maybe fall/ winter rides on occaision.

As far as racing level, I am athletic, but I am just returning to fitness and am working on establishing my base.  I am working to get fitter after many years without a regular workout routine, shedding post-pregnancy weight, etc.  For the forseeable future I think I will be a 'just for fun' triathlete, and work on improving my health, strength, and personal performance.  I don't think I will be racing competitively anytime soon.  Anticipate I will do several sprint-length tris a year, and hopefully upgrade to Olympic within a year or two, currently no aspirations beyond that.  In 5-10 years maybe, but by then I'll be looking for the next bike anyway.  I need a bike that will fit my needs for fitness, fun, and occaisional tris as well.

Where I ride:  I live in the foothills of the Adirondacks, so some seriously long hills and climbs on mostly medium, with a few high grades (as the Northeast goes, realize I'm not in the Rockies!)

I live on a big hill, so any ride starting from home (which will be 80% of my training rides) requires a hefty climb out, or back, depending on whether I head off up the hill or down on departure.

I know I want a women specific road bike with Shimano 105 components or better, I want top-notch steering and breaking, as I will be making lots of descents and aggresive turns on our windy foot-hill roads.  I want to be as comfortable as possible for 10-50 miles rides, and maybe an annual 100-miler.  I initially did not start out considering carbon, but rather a well-outfitted aluminum frame.  While shopping, I discovered some of the LBS in my area have closeout deals on carbon, I can get into a new Giant TCR WC1 or a Specialized Ruby Elite in the $1600-1800 range, so when compared to $1400 for what I've been looking at in aluminum, price-wise carbon may be within my reach, so I feel I have to consider it before making such an investment.

My concerns about the carbon:  Given I ride a lot of hills, (and will be doing tris with hills in all likelyhood) will I be at a tremendous disadvantage for climbing?  I hear one of the down-sides of carbon is that the flexible frame great for dampening road vibration also makes you less efficient when climbing as the bike absorbs a lot of your energy rather than transmitting it to your drivetrain through your pedals.  Also, crashing my bike...I know this is always a possibility, how rugged are these frames?  Does it take some serious effort to shatter it, or will it fall to pieces in a low speed tumble if my kid stops short in front of me and we have a minor collision?

As for the crank - I am currently on a triple, but I never use the biggest chain ring.  Most of the bikes I am looking at don't come in a triple...a paltry few do.  Will I be at a tremendous disadvantage going to a compact double considering the hilly terrain I will often be on?  Or will the difference (a few teeth I think?) be only a minor drawback until I build my personal streghth up?

Also, any thoughts given my needs, on low-end race bike or high-end performance bike?  It seems most of the brands I am looking at have at least 2 lines, one being their premier race line, and the other being their "performance" line...I believe (other than frame composition and range of componentry) the key difference is in the geometry, and sacrificing an element of aerodynamics and speed (with the race line) for comfort, and possibly endurance as a result (with the performance line.)  Any thoughts on which direction I should go with here?  My sprint-length tris aren't long enough to demand an ultra comfortable bike ride, but I want to also use the bike for long rides with my husband, or kicking around on lengthy (but low mile) family rides with the kids, so comfort is a consideration...how much difference in general between these two similar classes of road bikes?

I have been looking at the following bikes (I know there's lots more I could consider, these are the models my local bike stores have had available in my size):  Giant TCR C1 W;  Giant Avail Advanced 2; Giant Avail 1; Specialized Ruby Elite

I also want to consider (but need to find a dealer who has some in stock) Cannondale Synapse & 6 lines (appreciate any elaboration anyone can provide on the difference between these two lines), as well as Trek 2.1 or Madone 4.5.

Am I on the right track?  I want to be happy with my purchase for the next 4-5 years...but fully realize I likely will never be an elite triathlete.  I want to find the balance between buying more bike than I need and not scrimping now, just to find I need an upgrade in a year or two.

I appeciate any thoughts you can provide on my options.

Thanks!

-Heather