what im not getting at is why do you want/need to get smaller wheels(rims)???all you need is tires....go shop around at tire shops and get the ones made for all season or ones that work especially great for winter....dont degrade the looks of the car by slapping on way smaller rims.....the 17"s are fine....and the tires arent low-profile enough to make a difference, youll find that youll prolly spend as much money trying to get a 15" rim set + tires, as you would juss gettin tires for the 17's......IMO stay with the 17"s....theres a reason also why they arent smaller....because its not good on the car....keep the size or go bigger.....
i live in buffalo NY. there is a LOT of snow here, and 17" all season tires will still not perform very well.
My GF and I are exploring a few options:
if 4 all season R17 tires are ~400-500
if 4 15" rims are 100-150, with tires costing about 150-250 for a set.
These wheels will be for bad weather, not for summer, so the narrower, the better.
still debating which route to take myself, but thanks for everyones advice