Many good recommendations in this thread. At the end of the day, be it shotgun, handgun, baseball bat, or whatever, it's all about training and comfort. What your are reading is to be expected; intelligent folks who went through a careful decision making process based on their own needs, experience, and preferences. The fact that many came to slightly different conclusions, and the fact that there isn't a single answer, shouldn't be a surprise.
It's been recommended before, and I can't stress it enough - go take a class or two. The indoor range I frequent has a full selection of different handguns to try and yes, even a 12 gauge or two. Unless you have a friend close enough to walk you though this, and perhaps even if you do, there's no substitute for having a professional show you how things work, how to acquire a sight picture, etc. Basically, get you off to a good start. Shoot a revolver, a couple of autos, that 12 GA, everything you can get your hands on. My guess is that one will rise to the top and become the obvious choice for you and your needs.
Several folks, myself included, have offered to chat on the phone or PM. Just remember, Bruce, everyone is different and you need to make this decision based on your own needs and comfort level. When it comes to defensive weapons, one size most definitely does not fit all.
Good Luck - B.B.S.