RE: If you had to choose...
Ruger Super Redhawk in 44 Mag. is THE hunting pistol.
For the 2nd part of your question - I would stay away from black powder pistols, especially the cap and ball revolvers. The is no black powder pistol that I am aware of that I would even remotely consider for hunting.
They are a whole lot of fun to shoot but should not be considered for hunting.