I think I already know the answer to this... But..

Have you considered switching only one pedal to clipless? 

You're probably correct that recent experience has "colored" your thinking and your body works to fulfill the expectation that you'll fall.  To overcome this, focus only on the very next stop.  Think to yourself "I'm going to unclip my right foot and stand on my right foot."  Then do it!  Once you're riding again, marvel for just a second or two on your successful stop (to reinforce the positive experience).  Then focus on just the very next stop, not on the entire ride.  The reality is that a "good ride" is a series of "good stops" strung together. 

Hadn't really even considered having 2 different pedals..  But I will now.  You're correct that now my brain is in fall mode when I come off the bike.  I will consider your suggestions, though.  Thank you!

The foot is very close to my bike..  I could work on moving it out further.  I do think that would help.  I have always had anxiety stopping and getting off the bike.  Even on flat pedals I have a sort of cockeyed hop-off that I do.  Maybe I should put the flats back on and work on getting off of those the right way first. 

Well, I have fallen enough for several people.  So kudos to you   Given your successful track record, I will try this.  Are you on a roadie or a tri bike?  What kind of pedals are you working with.  Now I'm just being nosy, you see. 

It sounds like as you are about to put your foot on the ground, you need to tilt your bike (by slightly turning the front wheel ) in the direction of the foot you have unclipped and are about to put on the ground.  This serves 2 purposes: allows you to more easily put your foot on the ground and shifts your balance onto the free (not clipped in) foot, which keeps you from falling over after you've stopped.

Another thing you could try would be unclipping BOTH feet.  It'll take you a little longer to get going once the light turns green, but you won't fall over.

I'm on a road bike. I have Shimano pedals...don't remember the model. They were entry level. The bike is a Trek 2.1

Sounds like solid advice to me.

Thanks everyone.  I really do appreciate the advice.  I will try them all.    Not at the same time, mind you.. 

*ahem*..

On a lighter note:  I have decided my bike is ejecting me at the end of the ride.  That makes it funnier to me. 

How about practicing unclipping the left foot, keeping your right foot weighted (keep your weight on the right foot with the pedal at the bottom of the stroke) and leaning left?? I mean, if you are falling to the left anyway, unclip that side??

This is what I do. That way, the right foot, (which for me is the one I use to start the pedal cycle after a stop), can be left clipped in. I move my right pedal to the top of the stroke as soon as I have come to a stop so that it is ready to go.

This.   I'm so thankful to the guy at the LBS that taught me this from day one.  

One more thing - make sure you unclip your foot while you're still coasting.  Then slowly brake and touch down.

If you try to do it at the last minute right before you stop, you're more likely to get off balance.

My wife did this to learn.  She was also very uncomfortable with clipins.  After she got used to this sort of stop she later just unclipped the one to the natural direction she began to lean. 

I'll second a couple of things that have already been mentioned:

Unclip both feet until you get used to it.

Unclip well before the stop. Heck, I still unclip easily 25-50feet before most stops No harm in pedal a few times while unclipped...same as when you are starting off and can't quite get it engaged.

squirt - 2011-04-16 7:24 PM I just tried clipping in and out on a ride for the first time today.  Not knowing any better, I unclipped both shoes prior to stopping at several traffic lights, and thanfully didn't fall at all.  Once I was stopped, I then clipped one shoe back in before the light changed and was ready to just fumble with the other one getting started again .  So with my vast experience of ONE ride, I'd recommend unclipping both shoes as some others have suggested. Hope to someday be a big girl and unclip just one shoe...but baby steps will do for now.  

What?  Unclip both feet?  Never heard of that, even in training and while learning to use clipless pedals.

About 2/3rds of people unclip the right foot and lean right at the stop.  I think that's safer because if you fall over you fall into the shoulder not into traffic.   My wife is one of the left foot people, I don't like that because if your foot slides on wet pavement etc you fall into traffic. 

I recommend this approach:

Riding up to stop you prepare to stop by unclipping your right foot with the left foot at 6pm (at the bottom of the rotation).  Stay upright and your butt on the saddle. 

Since your feet can't reach the ground with butt on the saddle (usual fit), as you come to stop slide smoothly off the seat and put your foot on the ground, leaning slightly right. 

Put your left foot at 10-11am on the crank (just over the top) and wait for the light, etc.

To start, push hard left foot down to the bottom (6pm) while smoothly sliding back up on the seat.  You gave yourself enough momentum with that left foot that you're moving, and now your right foot is the top of the rotation (noon or just past it).  Clip your right foot in and push hard down right.

If you lose speed, just pedal with left foot in and right foot sitting on the pedal for a couple cranks, and try again.

EDIT: IMHO, SPDs are quite difficult.  Previously I've used LOOK pedals, currently I have Shimanos on my road & tri bikes and bought some cheapie SPDs for my mountain bike.  The SPDs are far more difficult to get in by feel.   SPDs are cheap so a lot of new riders buy them, but my advice is to avoid them in general.  There are many better designs.

Something to check... tension in the clips is adjustable.  It can be made looser or tighter.  Perhaps yours are too tight.

But, I also agree with the previous post. I had SPD and changed to LOOK.  Like them much better.