Yeah, I just finished up a shooting course where you would set your gun up with different types of jams and you have to clear them, reload and fire. When someone is breaking down your front door isn't when you want to be flipping through the owner's manual.
Most handguns break down into 5 or 6 pieces, so there's really no reason for someone to half-ass clean their gun. If you're depending on the gun to possibly save your life, why wouldn't a person take the time to do it right?
Everybody has different hand sizes and preferences. You need to make sure the gun fits your hand first of all. I've seen people with guns they couldn't handle, not much point really.
Probably one of the best guns I ever owned was a SW 686. It shot either .38's or .357's. That thing was accurate as hell. The drawback was it was also very heavy and it only carried 6 rounds.
I love my .45 though, as that's what I used in the military. The Marine Corps was just starting the switch over to the Beretta 9mm when I was getting out.
I didn't like that 92F at all.
I'd say a shotgun is his best bet. You can hit a damn target pretty easy especially if you aren't familiar with weapons. Also, if I'm a bad guy and I hear the shotgun get racked, it would intimidate me pretty bad.