Nightlife-
Breck
Sherpa and Yeti's - may be 21 and up, don't know. String Cheese Incident (spelling?) plays there a lot.
Breck brewery - assorted bands when I was skiing Breck, like 5 years ago
Keystone
Snake River Brewery - good beer, don't know ages
Dillon
The Ba - not a hippy/yuppy bar, more down to earth.
I am a nerd, so I don't stay out too late. I might not be the best resource for nightlife. All of the above, with the exception of Sherpa and Yetis, has good food.

Quick tip - check Skiing magazine and snow.com. If you are certain of the dates and location, now is the time to buy, good deals. Condos for lots of people save $$$. Packages avaliable right now too.

As for the backcountry, when you are ready you'll know. Backcountry just means out of the gate and untracked, not steep or crazy (although it can mean steep and crazy). I've got a couple nice easy runs perfect for the beginners off of Loveland Pass, when and if you are ready. Thats where I take my buddies. 1/2 a day of beacon training and digging pits and we are off. I am always the first one down anyway, so if it slides, it is me caught.