Just got back myself from a fly fishing trip. The weather was perfect and things are starting to turn green in the smokeys. Yes, it can be a bit harrowing driving in the smokies, but that's part of the experience. Just drive defensively and sensibly!
Of course, the water park at the resort will keep the younger family members occupied. Downtown Gatlinburg is a major tourist trap; countless tee-shirt shops, shows, and other stuff that we try to avoid. The traffic in downtown Gatlinburg can be chaotic; carless pedestrians, double parked cars, on-going construction (some going for 3 years now), and lots of people. But some park and walk through Gatlinburg (at least once), for the experience. Oh yeah, use the bypass around Gatlinburg to get to/from Pigeon Forge, it will save about 20 minutes travel time.
You'll want to take the drive through the park down to the loop in Cades Cove. Along the way you'll travel along the Little Pigeon and Little Rivers, Abrams Creek and other small streams. Very scenic with lots of trails and pull offs; hiking trails, overlooks, waterfalls, etc.
You might want to take the drive from Gatlinburg through the park over to Cherokee, NC. The views are spectacular near Newfoundland Gap, we saw plenty of wild life along the way and the clouds clinging to to the mountain tops are something the family will remember forever. There will be lots of opportunities to take pictures with the family.
Traffic going through Seiverville to Pigeon Forge will be heavy Friday evening on the main road; and then again on Sunday evening going the other way (people leaving the area and heading north). So we try to avoid these times if possible and stay off the major routes. When we were there last week, it seems like they finally synchronized the stop lights so traffic at least moves now; but it can still be bad at times.
Enjoy the park, it is really well kept and managed. We try to get there at least 3 times a year for the fly fishing and hiking.