a week in Madonna Di Campiglio for skier and non-skiers

So I'm organizing a group ski trip to Europe and narrowed down my choices of destinations (based on a US tour company that I want to use) to Innsbruck, Interlaken, Madonna di Campiglio and Val Di Fassa. The price for flights, 7 nights in a hotel and lift tickets are all relatively similar.

The big question is...is there enough to do, besides skiing/boarding, to keep people entertained for a whole week, especially those that are not skiing. And those that are not skiing are also probably not going to be doing snow-shoeing or similar activities.

And how's the nightlife? At least over a weekend? Good bars and (maybe) clubs to go to?

Is it "happening"? fun?

oh and if you want to comment on the skiing for 4 out of 7 days, that would be helpful too. Do you get bored by the 4th day?