What Wyosmith told you in post #9 is very true and very good advice, I agree with what he says.
Here's my thoughts on what gun to purchase other then a shotgun, however a good short barrel 12ga pump is pretty hard to beat as a home defense weapon.
You made the statement whatever you choose may be for home defense as well as concealed carry.
If there's a gun store with an indoor range near you that rents guns, go rent and shoot as many different models as possible.
If this is not possible contact friends that may have several different types of handguns in different calibers and see if they will let you shoot them.
The ideal is to try as many different calibers and handguns as possible to find what works best for you.
Whatever you choose, practice using your handgun until the handgun is an extension of yourself and you are very proficient with it, this includes safe handling skills.
If you do this, guns with safeties are not a problem.
As a matter of fact if you choose a double action gun with a heavy trigger pull and don't practice you will most likely shoot low with it and miss what you are shooting at completely, this is not good in a gunfight.
Follow the advice Wyosmith gave you in post #9, along with that you can't train to much for a bad situation, and when things get bad use what's between your ears, keep thinking.
In closing I hope you are never faced with having to take a life to defend a loved one or yourself, it's not a pleasant thing.
Best Regards
Bob Hunter
www.huntercustoms.com