What's the Best Handgun?

I relize that this is a rather difficult question, but I still want to get some opinions. I know a fair amount about rifles and have more than enough (if that's possible). However, I know very little about handguns and I would like to purchase one mainly for self-defence.

Basically I am looking for a pistol with a great deal of accuracy (I plan on target shooting with it) and in a good caliber (one I can use for target shooting/self-defence).