K.B.
Love love love the area. My parents have a home near Beaver Creek adn we love the drive to Glenwood Springs. There is an awesome hot springs pool, with very cool slides the kids will love, it's a great place to spend a day. My husband and I always find time to pop into Yampah for spa work, they have vapor caves down below that are like steam rooms, albeit rather stinky. You are also equidistant from big resorts, Aspen to the west and Vail/Beaver Creek to the east. On the way to Beaver we have a wonderful time at 4 Eagle Ranch, which has a BBQ and horse rides and live music (http://4eagleranch.com/). Both Vail and Beaver Creek have a ton of free activities in the summer, from concerts to the Free Fridays at Beaver Creek Park Hyatt with smores and music.
For Aspen: http://www.allaspen.com/summer_recreation/
It's lovely, you're in for a treat :)