Vail (this time of the year) is going to cost you your first born. I agree with Estes Park (The Stanley). Absolutely beautiful up there, but there isn't much night life to speak of.
You might even consider Fort Collins. Great town (Colorado State) and the night life is really nice. Great restaurants, walking distance to everything (in the downtown area) and the people are friendly as hell. The traffic can get hectic at times, but not really a huge deal.