I personally trust long wheelbase 2wd trucks in the winter far more than fwd cars. Short rwd trucks suck though. They fishtail far too easily.
Term, BFG Load E All Terrains or Mud Terrains are probably your best bet on tires. Do what you want to as far as wheels go. I'd go with 16" if I were you, but in the end, it's your truck, not mine. As long as you like it, it's all good. Just be aware of the pros and cons of each setup before you buy.