We stayed there for I think six days, at a cabin we rented from a friend of the family. Most of the cabins there offer the same, though. There was plenty enough to do for the whole week. Like I said, we did the national park for probably three days. There are hiking trails, Cade's Cove loop (which you drive), waterfalls, etc. And during the summer, the beautiful creeks make for great swimming holes/tubing courses.
Pigeon Forge is full of shows, similar to Hoop Dee Doo. Black Bear Jamboree is a dinner show with musical acts (when we went it was a tribute to every decade of music). Comedy Barn is a very fun, family-friendly comedy show set in the Hee-Haw style. There's a Dixie Stampede show, which is a country and western version of Medieval Times (or so I've been told). There are other shows we didn't really explore also. Besides that, Pigeon Forge's main drag has tons of miniature golf courses, arcades, go-kart tracks, etc. They do have a Christmas Village place (can't remember the name), but the day we went there was a Santa Claus there and plenty of free activities for the kids (face-painting, balloon animals, card-making, etc.)
Gatlinburg has a pretty cool main street with lots of shopping and museums. There's a car museum, Ripley's museum, another wax museum. Oh, and lots of fudge places. LOL Gatlinburg does have the Ripley's Aquarium, which was a pretty good experience. Gatlinburg is themed like an old German village, so the buildings are all close enough to park and just walk up and down.
We liked the trip there enough to probably put it into our rotation of non-
Disney vacations. It's a little on the expensive side, IMHO. But that's coming from a guy who believes the biggest bang for your vacation buck is WDW.