I have owned several revolvers and for me,I think 4 inch is best overall,6 inch at the longest.Longer than 6 inch just get a short rifle,its not much harder to deal with.If you wanted to stay with your first idea a S&W .22 in 4 inch is really nice,shoots good,holds value,you can be proud to show it to a friend when they ask what you carrying.I have been around the horn a couple of trips and for fun and something that will do 90% of what most people wind up doing,a good .22 is hard to beat.
For hunting a .22 hollow point is recommended.Solids just don't work near as good,a Stinger for example is a good round for varmints at close range.