Ameristar is definitely the best hotel in Black Hawk - good choice. Your daughter will love the roof top pool. But not a ton of other non-gambling stuff in Black Hawk. The town itself is neat....most of the casinos are in old gold mining buildings. They've kept those pretty historic, on the outside, at least. Rafting on Clear Creek is amazing! If you have time, try to take a day trip to Vail. It's only a couple of hours away from Black Hawk and worth checking out.
Estes Park is always fun....small town, so not a ton to do there, but RMNP is amazing. Are you going into Denver at all? Check out the 16th Street Mall if you do. Lots of shops, restaurants and other fun stuff to check out, things a 17 yr old girl would love.