It seems that I've heard people say to just buy a second set of tires/rims for winter driving. Most all-season tires don't handle well at all with heavier snow, etc. Honestly, I think its a good idea too unless you want to run on snow/winter tires all year long, but I know you get some decent weather in Boston in the summer.
I have a set of 225/60R16 "Semprit" snow tires. They are another line of Continental tires. They worked wonders for my car in the winter and rain. Honestly, I think my car deals with wet weather now better than my dad's '00 Lexus ES300 (FWD) with all-season Toyos. Weren't too expensive. I got them for $79 installed each, but I would assume they'd cost a bit more for ya.
Another really good tire that I was going to buy except I couldn't find them anywhere is the Firestone Winterforce II M+S. They are extremely cheap and a good tire. Couldn't hurt anything to pick up a cheap set of 15" rims from someone and buying some of these. It'd probably cost you under $300 total.