Quite frankly Whatever is closest becomes your favorite weapon real quickly if somebody is invading your home, armed or not. Looking at hard numbers? Shotgun spreads at 5-10 meters with buckshot? yeah the wad probably holds the spread together pretty well, As far as a pistol goes? If it's a .45 Expect it to go through a piece of drywall. Expect a .22 to go through drywall. As far as military training takes me in terms of close range combat with a V.I.P or hostage situation? Shotguns are a big No-no. Your odds of FF or hitting civvies goes way up. these high caliber pistols people keep going on about, I'm not convinced, There's this little thing called recoil, and it royally sucks on a .45 or whatever else your shooting, And everyone should know that the more recoil you have, The longer it takes for you to place more shots. I personally would go with the AR-15 platform only because it's similar Specs to the M16A1 rifle. I was trained and deployed with the weapon, So naturally it would be my first pick in a fire fight. So my conclusion? AR-15 would be my first pick if handed to me, Why? Prior training, Attachments for better placed shots, Flashlight accessories, and minimal recoil not to mention if you have a 30 round clip, You should have enough ammo to push through a firefight if your not a complete ****-tard and unload on your couch.