As for the best gun and ammo, it depends on the person and how the gun feels to them.
In my case, I have a Mossberg 500 12-ga. pump with 3 inch shell loaded with 6 shot turkey loads. (I live in an apartment). I also own a 1911(Rock Island) .45ACP which I can also use for self-defense.
For the record, I'm not a gun expert(I'm more involved in the political end of it as a freedom issue), nor claim to be one.
Thanks for the input.