Hogdogs, down here we trap the small ones and pen em up. Then, whenever a good saturday comes around, a hog or two goes in the pit. Your right, there is rarely one over 100 lbs, the big ones are too smart.
Where I live, theres two different kinds of habitat: open flat scrub, where they can see you from miles away, and swamp, where they sleep all day and only come out at night. If im stalkin in open scrub, I use a 30-06. Ive never had a problem with putting one down with that, and it has the range for long open shots.
For in the swamps, we go out at night on a buggy and spotlight em. I usually got a marlin 45-70, or just a handgun in .45 or .44 mag. Those are all sufficient enough to put down any good size hog from close up. Just make sure you got a gun that holds some rounds, alot of times you gotta take multiple shots.
As far as eatin size, hogdogs was pretty spot on. There aint no bad pig, its just how ya cook it up.