I've actually been lucky in December and January with the snow, but avoid the Xmas holidays like the plague. A-Basin is quite nice, I personally also like Keystone and Wolf Creek. I didn't like Vail, and the $15? $20 parking was an insult.
For a 'controlled' backcountry experience, Silverton is the place to be. And don't drive from Durango the day of your reservation, you've got two mountain passes to navigate. Stay in Silverton, it's way atmospheric, almost ghost-town like, and make sure you're physically ready for some seriously high-altitude hiking.
Darn, that hiking almost killed me, and I had been exercising at 7300 feet for a full week before that.
For an alternative, spring riding is fun, so April would be my second recommendation.