Revolver Pro's: Reliable, can handle rounds that are proven animal stoppers, carry nice, can be fired double action in a spur of the moment situation.
Con's: Limited number of rounds but in a situation very rarely will you have time to get all 6-8 rds fired off, they cost more than a Glock.

Semi Pro's: Can be reliable, some decent calibers for animals, magazine capacity.
Con's: Can be finicky, most calibers don't lend themselves to animal cartridges, require a little more learning curve in my opinion.

Calibers:soft point,
.357 Magnum: Can be had from 110 gr bullets to 180 gr in solid, soft point, hollow point, lead, and shot shell. Since the .357 mag is in a revolver then you can shoot .38 spcl in it too.

41 Mag: Great rd, but a handloader cartridge for sure.

.44 Mag: Can be had in loads from 180 gr to 240 gr. in the above variations. A .44 special can be used out of it too. Follow up shots are harder to master since it can be a real kicker.

.45 Colt (not ACP): Probably not the best because most loads are for cowboy shooting and reloading is needed to relize the true benefits.

9mm: Not a good animal stopper.

.40 S&W: Pretty good man stopper but not great for dangerous animals. Plus side is the amount of rds that can be fit into a Glock 22---15 plus another in the tube.

.45 ACP: Great man stopper, decent animal stopper. Problem with he ACP is that it is moving pretty slow. Not the greatest thing when being charged by a wild animal.

10mm: Best option in a semi auto that I can think of. The ammo can be had in solid, hp, lead, in between 125 gr to 200 gr. The 10mm is zipping, and was the father of the .40 S&W. A Glock 20 holds 15 plus another one in the tube.

Guns:
Revolver: Colt or Smith without a safety lock. I carry a 5" S&W Model 27 N Frame with 158 ge JSP a lot of the time. I am thinking that a Redhawk in .45 Colt will be my next but I do handload.

Semi: Colt makes the Delta in 10mm but pricey. Glock, as mentioned before, is a 16 rd go getter. Nice thing about the Glock is you can order a spare brl in .45 ACP for the G20 or a spare brl in 10mm for the G21, spare mags, and have 2 pistols in one. On top of that, get an Advantage Arms .22 LR kit with some spare mags and you have all bases covered: .22LR for plinking and small game, 10mm for hunting and self-defense, and .45 ACP for Self and Home defense. The Glocks come in a slim frame version, and even a compact version. I will be ordering a 10mm brl and mags for a G21 as a birthday gift come March.

I hope I did not confuse you too much, and if you have any questions ask away. You guys help me out all the time with stuff so the least I can do is help in the firearm advice.