Some people judge the .22LR from the size of the hole and the lack of penetration. That's a mistake. It's like judging a shotgun by the performance of the pellet. The .22 should be judged by the [number of holes] + [the inherent accuracy of the round] + [the speed at which they're made] + [the paths they take in the body] + [their velovity].
Any defensive firearm should be judged first on the basis of penetration, and then on the number of hits that can be made timely.
The size of the hole is also important, but within the category of service arms (say, .38 to .45), it is of secondary importance.
Inherent accuracy really won't matter at all in defensive shooting...
combat accuracy is what is important.
The capability of a firearm to effect a stop other than a psychological one will depend in a large extent on what is destroyed inside the body. The first prerequisite is
penetration.
Precision accuracy won't matter. The defender
cannot see the critical internal body parts, and if he or she could, he would not have time to try to target them. Hitting them is a stochastic matter.
Velocity only matters insofar as it affects penetration and expansion.
One other thing, Confederate: your "don't talk to the police" links provide good advice for incidents
other than defensive shootings. But not for persons who will end up truing to mount a defense of justification. refer to the stickies in the ST&T forum for more on that.