It depends on what you like to do. In town (Pigeon Forge and Gatlinburg) there are a lot of shows and shops, and around the area are a lot of places to go hiking, fishing, birdwatching, etc. We only go to town occasionally (usually in Gatlinburg), spending most of our time hiking when we are there so I can't speak much to that aspect of the area.
I would definitely suggest going around the Cades Cove driving loop (the earlier the better, it gets crowded in the afternoon and won't be worth it.) The Roaring Fork driving loop is also worth doing - both have many historic houses and buildings to see and neither require any hiking unless you want to but you can see quite a lot and get a feel for the natural aspects of the park without much effort. Clingmans Dome and Newfound Gap overlook are also good for that, just be ready for some uphill walking to get to the observation tower at the Dome (it's all paved.)
- Randy