I regularly shoot pistols and shotguns and am fairly capable with both. Pistols we shoot at 17 yards, target is a popcan, not a problem with the longer barrelled .22 handguns but a little more difficult with the short barrelled concealed carry type handguns. Even so, if I miss a popcan at 17 yards I'm sure I'd still hit the body...
I shoot a lot of clays from all different angles and am just much more comfortable with a shotgun in my hands. That and the fact that my winchester model 1200 has NEVER jammed on me makes it my pick for home defense. I might appreciate the spread in the dark. But like another poster said, I keep all guns unloaded locked in a safe downstairs, so its not too practical that im getting to them in time. We have a dog security system but I sleep like a rock.
Basically to me its whatever you are the most comfortable with. Doesnt matter what the gun is, what round you use, what the risk of over penetration is, how long the barrel is, semi or pump, revolver or not, the bottom line is that you will be shooting at someone and you will need to do it with gun you feel the most comfortable with.