I asked the shooting question after my house (Queen Anne) was broken into for the second time.
The policeman said the same thing as (shoot I forget now Steely D?). If you are going to shoot em make sure they are dead. If they don't have a weapon put a kitchen knife in their hand.
Never shoot a teenager.
Never shoot an intruder in the back.
That said I don't even keep a gun upstairs anymore...I've got a five year old and it's just not worth it. All of the guns are in the safe in the basement.
So while I say I'd shoot an intruder it would be tough to do with the guns locked up.