I'm running 33x12.5 Goodyear Wrangler MT/R's, they kick absolute butt in the snow, particularly when aired down. Usually down to 18 psi on the street (in snow), 10 psi out in the woods. 2wd is hairy, but if you're running around in 2wd in the snow and ice on the street, you're just asking for trouble. In dealing with a few people that like to do this, the need to project machismo seems to be the common theme. You look like a tool either way - you made it home in 2wd? Wow, you're an idiot for taking the risk, especially with the magic get-your-ass-home-safe lever a foot from your right hand. Or you creamed some old lady in a Lexus after spinning out - good job, Slick! Why not just give Darwin a swift kick in the junk and lock it in 4wd? Meh... Whatever. I like my Jeep. I like not having broken bones or a pending lawsuit.
As far as tire width is concerned, the type of snow you're running in will be the determining factor, and unless you deal with snow for more than a couple of weeks a year, I'm not sure it's worth consideration when buying tires - especially when the condition of the snow changes often. My tires seem to work well on pretty much everything, though they're not quite as comfortable on heavy, wet slop. I'll deal with any negatives that may come along with my slightly wider contact patch in the snow, since the rest of the year they're ideal.