my winter beast is an IGH disc brake hybrid. i've equipped it with schwalbe marathon winter studded tires and full fenders.
the IGH is less than ideal (it's an alfine 8 that's lubricated with grease that can get draggy in cold weather), but otherwise it gets the job done.
many winter riders say they prefer a more upright style bike to put more weight on the rear wheel for better traction in slippery/icy/snowy conditions.
my first winter bike was an old hard-tail that i put a rigid fork on; that's probably not a bad starting place for many people.
winter riding can be ridiculously filthy at times (at least in chicago), so whatever bike you choose, i'd highly recommend one that can accommodate full fenders.
Last edited by Steely Dan; 08-26-16 at 11:11 AM.