Good advice from everyone. Be aware that any round fired that misses, can go out through the wall of your house, through the entire neighbor's house if it's lucky, and even enter a third house before stopping. It happened here in my neighborhood. It wasn't me. It was only a 22cal, and it was lucky. Not only the sound of a magnum revolver can be overwhelming, but the flash in a dark room might blind you from firing again real soon. But it does the same for your opponent. The sound of a shotgun loading is said to make half the opponents run, and the other half freeze. But that is for LEOs, I have no idea what happens at home. If I lived in a neighborhood where firefights were common, I think I'd move. You can always come back to visit a firefight. Target identification is as important as anything else. It's often in the dark. That's why everyone is saying a flashlight or two is just as important. You must identify what you are shooting at. That requires bravery, quickness, and intent to defend quickly. That means practice moving around in your own dark house. Find the places that provide cover from being visible, and hopefully cover from return fire. Sounds extreme, but it's necessary to survive. This part has to be thought out ahead of time. There will be other things happening to distract. Vocally challenging the intruder to stop, surrender, or run is probably necessary if you can't make a positive visual identification. Sometimes they tell you to go back to the bedroom and let them take your stuff, that's identification. Consider motion detection lights that spotlight your entryways or windows when something moves. Or gives a silent alarm, so you can move into position beforehand, and watch the fool with confidence. I like revolvers. They are stupid proof, I don't have to be awake to use one. I tend to think that 5 or 6 rounds are enough, but I'd be wrong. The best world is to have a revolver and a large capacity semi-auto. And I suppose three hands to hold them and the flashlight. Practice. I don't like magnum revolvers. They really aren't for a one handed grip on most people. I can do it, but the muzzle tends to jump and shoot high, missing the target. It requires concentration and lots of practice. But most magnums can be loaded with less powerful rounds, making them easily controllable. Then I like them a lot, the extra weight makes them extremely controllable. I'd stick with what is known to work. 38cal and 357cal revolvers, and 9mm, 40cal, and 45acp semi-autos. And practice often. Just be aware that any shot can leave the area and go down the street, through the wall, etc. Shotguns with birdshot will not go very far, but can still go through the first nearby walls and wood that it finds. And there really isn't anything wrong with a shotgun. A short 20 gauge or 16 gauge shotgun, instead of a 12 gauge, is a lot easier to control, and would work extremely well. And the kids can be taught on a 20 gauge. I really don't like just the pistol grip on a shotgun, but it does work better inside the house. It's just harder to aim. Practice. If you can't turn around in a hallway while holding a full length rifle or shotgun, without hitting the wall, it's a problem. Get with someone, and try various pistols and revolvers (and shotguns) till you find what you like and want. Rent them at firing ranges if you have to. And have fun, if you don't like doing this, it won't work out as well.