Raccoons and large possums are the largest things.
The biggest is probably a deer. Although you would have to hit it in the head.
Elephants have been hunted successfully with a .22 rifle.
A 275-lb man. If you place the shot just right, a .22 could kill anything.
Rodents and small game.
Animals as big as the Grizzly Bear have been shot with a .22 rifle. I do not recommend it, since the bear is likely to eat you. .22 rimfire should be limited to small game in the rabbit-size category.
None
You use a 22. rifle
Biggest threat is a landowner with a 22 rifle or 12ga shotgun.
Normally a 600-700 fps air rifle will kill a rabbit at around 30-40 yards away. So this will include a .22 caliber air rifle or if your looking for something with less power that will just kill birds, try looking for a .177 or .20 caliber air rifle but if you are looking to hunt game like rabbits go for .22
Definitely Yes.
Yes. But I suggest using hunting pellets.
Definitely Yes it can.
Many would say the 22 Long Rifle.
That's a very vague question. If you mean a .22 caliber rifle, the techincal answer is, almost anything. It's possible for a .22 to kill almost any animal, it just isn't extremely likely in some cases.