Well, we can't carry anything here in France but I'll play along!
Of those I actually own, there are three I would use depending on circumstances:
If I went on, say, a fishing vacation in Alaska, it would be my Ruger Blackhawk in .41 Mag.
I don't have anything bigger at the moment, though it could be argued that a stout .45 Colt is just as good..
Anywhere else, I am very partial to the Single Action Army. I probably wouldn't use my 1st gen Colt in .38-40, being worried about losing it, but my Uberti El Patron in .45 Colt would be one of my two choices.
Let's see the TKO between .41 Mag and .45 Colt (both 4-5/8"):
.41 Mag : (210 x .41 x 1350) / 7000 =16.6.
.45 Colt : (285 x .452 x 875) / 7000 = 16.1.
Not much of a difference if you trust the Taylor Knock-Out system...
Then, if a big bore isn't warranted, like around here if it was allowed, my S&W 586 in .357 Mag.
TKO: (158 x 1350 x .357) / 7000 =10.9. Anything ten and above really is good in my book.
The 586 allows for faster reloads of course, and that could be a big factor depending on the threat.
Since we are talking about woods guns, assuming animals, here would mean maybe wolves, though they seem to be pretty elusive, wild boars or packs of feral dogs. I've seen wild boars, but never groups of dogs, and surely no wolves. Anyone killing a wolf here might wish he had rather been devoured than found out, as the legal repercussions would probably be worst than a quick (hopefully) demise... Anyway, it's a moot point, but fun to imagine hypothetical scenarios.
Now, if I could buy anything I wanted as a woods gun, independently of price or import difficulties, it would be a Freedom Arms 97 in .45 Colt with a 4-5/8 barrel. One day maybe... Not because it necessarily would be the best gun for that purpose, but because I really want one!
Gil.