I've worked on a number of killings with .22 LR ammo, and a number of shootings that did not result in deaths. Immediate stops are possible, and are attributable to the same things that work with other calibers: shot placement and adequate penetration.
Adequate penetration is a real issue with .22 LRs. I'd go with hi-speed 40-grainers. Chrono a mess through YOUR gun and see what comes out fastest.
Going with lighter weight or hollowpoint bullets seems like an invitation to have even more problems with penetration than a .22 LR has inherent to its slow (particularly out of a handgun), light bullets.
FWIW, I'd use CCI Velocitors - they consistently chrono the fastest average (tho with high deviations) of .22 LRs from handguns for me, and they're 40-grain solids.