Hopefully this is the place to ask about the best home protection hand guns. If not,

[littlewolf]

65. came late to the party .. but here is my 2 cents

IF is has to be a handgun ... I would go with a revolver .. Double action ...
it doesn't jam ... doesn't "stovepipe" and is very reliable ...
I would get a minimum of a 4 inch bbl for muzzle control and accuracy ...

I would get a 38/.357 probably in Ruger (my next handgun will get a SP101)

this gun is easy to clean and maintain ... it will require you to go to the range
and practice but no more then any handgun

that said ...
semi-auto's are good .. they may take a little practice to be comfortable with ...
cleaning them is a little more involved
I recommend at least a 9mm .... if you want something a little bigger
.45 acp is excellent ... but if you are a smallish person you may want to stay
with the 9mm .... less recoil .... and in most cases 16-17 rounds ....

with this weapon you will also need to go to the range ... there is more to master

I would recommend a Glock 17 .... excellent firearm ( I am biased toward Glock clean simple and easy to use ...)

but hands down the best home defense weapon is a 12 ga shotgun with a 20 inch bbl ... pump or semi-auto ....

hope this helps ....
all the information in his post is excellent and a lot to take in ... take your time
and be comfortable with the weapon ... most ranges will rent you different guns
to practice with and get a feel for .... in many cases they will have someone help
you when you are on the range .... safety ... stance ... breathing ... all of it ...