I'm lazy and I buy performance all season tires. Grip well enough in the dry/wet to not be of any concern @ stage 2 power, and they are 'passable' in the snow - you do have to be a little more cautious then you would with an actual winter tire though and I definitely suggest you are comfortable in snow driving before going that route. it is preferred to have a winter set and I would change over to them in late Nov / Early Dec, and make the switch back in March sometime. depends on the year.
fyi - I do snowboard and I do drive in the snow. I got around in some falken 512's just fine. I am now running hankook ventus H105s, great wet/dry performance so far, only time will tell in the winter.