I currently have a .38 S&W that my father gave to me. However, I am looking to buy a new handgun so I have a nice carry before I turn 21. (I am 20).
Right now, I believe one of the best would be the Walther P99 .40 Caliber Quick-Action
The other would be a bigger gun...one that not many people own, but have heard it is a FANTASTIC gun, and extremly accurate.
The Baby Desert Eagle:
Which is by no means a "baby".
The other would be an H&K Compact in .45 which is a very good gun (clearly since it's H&K)
And now...here's the odd one..but I really think it's a cool gun and have heard some pretty good things about it, in fact, it just won the NRA 2008 "Golden Bulls Eye Award" it fires either .45 caliber, or .410 shot shells\slugs. Ideal for being car jacked since you just point it out the window and bam spread shot. Also useful on the trail in case of snakes, etc.
The Tarus Judge Revolver:
Out of these, what do you think? The lightest, smallest one of would be the Walther. This will be for carry\personal protection, open and concealed.