Niner tires will generally have a slightly more oval contact patch and sixer tires will be more round, if the tires are similar in other attributes. I've never found 26" tires to be slow, and I like short wheelbase bikes, so I roll 26" on MTB. Well, that and around 500g XC tires instead of ~700g XC tires.
Berman, if I were you, I'd buy two nice, rigid mid-90s MTBs for around $100 apiece and DIY stud the tires on one of them. I actually just have one front DIY studded tire and get around fine, but we only have a few snow days a year, so maybe just buy one used MTB and a spare front wheel if you think you can get by like that.
Oh, and if you wanna single speed it, it's often pretty easy. This one was really close to hitting the magic ratio with 34x15. It's a little tight, though so I'm gonna file out the fronts of the rear dropouts a bit to relieve some chain tension. I think I might go drops with this one as I scored some of those $10 EA50s @ Jenson. Just need to dig up some brake levers and stem.
Kinda depends on length of commute also. Shorter commutes I'm fine with flats/risers. Longer ones I want drops. So far this bike cost me $5 for bike, $13 for bars, $5 stem, $3 for grips.
