While true that bullet design does make a significant difference in the effectivness of a bullet, volocity also effects it. Even a hollow point, if traveling to fast will simply splinter in to very small fragments. Even small fragments cause trauma but usually not as lethal as a large object pushing through taking flesh and organs with it. 10mm hollowpoint is a perfect example. At close range bone will cause the bullet to shatter where as a .40, though the same diameter having a lower volocity with simply deform but hold together.
That's not necessarily true. Just because one 10mm bullet will frag does not mean another from a different manufacturer or even a different lot will. In pistols, velocity difference is not really so huge that it causes these types of issues. I have seen two different people shot in the head with a .40 and the bullet ricoched off of each one and only wounded. One was from under water which probably led to external ballistics issues, and the other was a forehead shot, but those bullets were later recalled due to some type of bad jacket bonding process. That does not mean all people shot in the head with a .40 will live or that the bullet is inneffective.
My .223 will beg to differ with you on the 'small fragments causing trauma but not being lethal' argument. I'd rather take a .45 to a body part before a .223 to that same part. If you think I am wrong, shoot a gallon water jug with any pistol you want and watch the effect. Then shoot another full jug with a rifle bullet and observe the difference. Same as always; lethality is dependent on PLACEMENT.
If you want to defend your house and want to reduce ricochets but still stop intruders, invest in a pump action shotgun. Almost any guage will do if you run dove loads or even bird-shot in it. Just the sound of a round being racked into the chamber is enough to stop most people, but if not, close up, pellets are lethal and at distance the noise and wounding factor will get the point across.
Lastly, it is probably never a good idea to share your plan for killing someone, in your house, on a PUBLIC internet forum. If you ever have to resort to lethal force and someone finds out about your "plan" the word "premeditated" will become a big part of both the civil and criminal trial.
WOW...This really has gotten way off topic.