I know a cop who recommends the 55gr AR as an ideal home defense weapon. I would not agree since if it was accidentally loaded with 62s it would go through two houses.
All of this stuff is conjecture since most of us have never dealt with a home invasion. I would say that a Ruger 10/22 in the right hands would stop any threat if used aggressively. I can't imagine what it would be like to get shot with a load of #8 birdshot from 20 feet away, It would be awful I know that. It would take a lot of sand out of any intruder. If you wanted to make sure, the guy isn't going to be doing much after that, so shot#2 would do the trick. I have been using a Model 39 as a home gun, it is accurate and works. I would use a 1911 except that I don't want to risk losing one to some homeless tweeker who stops by when I'm gone. With a 45 I WILL kill you everytime, hit you and kill you. Around here, the marijuana growers and the trash that follows them has made a once safe place into a risky place. I would be more concerned that a home invasion would involve several people. Having another weapon or magazines handy would be the most important thing. People who have been shot hard, in the torso are in deep trouble within seconds regardless of the gun used. In the war people who were shot but not fatally, would go into shock and die anyway. So I'd say, have a weapon that you can use instinctively and effectively and pay attention to what's behind your puke. Ever round has your name on it. If your rounds didn't have the desire effect, shoot the guy again. Most asshats that break into houses are gun stupid.