CowboyT wrote:That's assuming one doesn't practice and therefore can't shoot.

In that case, get a compact semi-auto. You can get 10+ rounds in some of those.
"It ain't the arrow, it's the Indian."
EDIT: Upon further reflection, this might've come off a little harsh. Let's see if I can try that again with a little more thought.
The main thing is practice, practice, practice, no matter which firearm one chooses to buy. Firing quickly with an LCR, I know that I can nail an 8.5x11 paper at self-defense ranges all five times, and I teach myself to aim for the center of the chest, like the cops have told me to do. I can do this because I typically go practice several times every week. Firing two rounds of factory .38 Spl +P HP's is likely to do the job on an assailant. If there's another two or three assailants, then typically they're going to run like the wind after the first shot is fired. If four or five guys are taking you on, then you've got bigger problems anyway, which I seriously doubt an extra round of .327 Federal Magnum will solve.
Unfortunately, too many people who carry do not practice with their carry firearm. This is bad news. If one cannot hit one's target, then why is one carrying the gun at all? Proper marksmanship matters. "A hit with a .22 is better than a miss with a .45."