MK...

Are you using toe clips or clipless pedals? Toe clips are easier to get stuck in, in my experience, than clipless. Even seasoned riders can get get caught off guard and not un-clip in time, but barring that situation, your clipless pedal system itself should be reliable and foolproof, or you need to examine your system. I've been there with that panicked feeling when your clip isn't releasing!

I've tried several different pedal systems from Look, to Speedplay to Crank Brothers. I'm a serious road rider and after trying a lot of pedals I ended up with Crank Brothers eggbeater pedals (the good ones - not the cheap ones). A pedal doesn't get any simpler or easier to use and I can *always* get un-clipped. The added benefit is that it is a mountain bike pedal and the cleat can be fit on shoes with a recessed area, so you don't have a problem walking on them.

Even so, I recently got a new pair of Keen cycling sandals for my commuter ride, and had trouble un-clipping... not a lot, but enough that I had to think about it and it ruined my first ride. A spacer (that came with the cleats) solved the problem.

I have several friends who have Speedplay Frogs and love them while I did not, so there is a pedal for everyone. But if you have to think about unclipping in just the right way, then I would advise to examine your pedal system. Maybe you just need a spacer, maybe your cleat is not tight, maybe your shoe is too loose, maybe you have them set too tightly (on some pedals systems), etc. But they should be easy to get in and out of.