I have put alot of thought in to this and I know it is a matter of preference for most.
I think for personal protection, hunting, and in general a "if I could only have one gun what would it's caliber be" thing I would choose the 44 Magnum.
You can shoot low recoil 44's in it all the way up to Buffalo Bore heavy 44 mag. +P's. You can shoot shot shells in it that are as potent as a .410 shotgun.
There are alot of factors involved in a decision like this but at the top end you would want something that will stop a 2 or 4 legged beast with one shot and also hunt small game on up to the largest.
I think it's a good choice.
And I would want a Ruger SA to go with the round, for durabuility and longevity.