I have decided on a snubby .357 mag (or my blackhawk .357 for REAL deep woods/REAL bear country), 1-2 rds of snake shots (snakes are mostly what I'm worried about... and people) and then 3-4 personal defense rounds. I have a rottweiler and pitbull hiking with me so they should ward off most natural creatures... and people.
I would not worry too much about snakes; they really have no desire to be around you. If you have enough time to draw and shoot a snake, you can walk around him.