We stayed in the Smuggler's Notch resort for a week about 6 years ago. It was beautiful in the summer. The drive through the mountains itself was worth the trip--it truly looks like an enchanted forest!
Anyways, during the vacation, we went to Vermont Teddy Bear company, Ben and Jerry's, and rented bikes to ride through the bike trails in Stowe. We went on a few of the optional trips that Smuggler's Notch offers--a lunch canoe trip, for instance. It was a great vacation--and off-season, so much fun.
The resort has a lot of planned activities for the kids. . .late night singalongs, barbeques, etc. There are lots of daytime activities, too.
We had an EXCELLENT time. And, everyone was so nice!