I live in Nashville, so when we drive down it's through Atlanta. In my experience, it seems the only good time to go through Atlanta is in the middle of the night. Traffic is horrific. Take a bathroom break in Marietta (north of Atlanta), stay in the HOV lane, and pray there are no accidents or construction. Sometimes, it can take an hour just to get through downtown. Another option is to take the by-pass. This takes a long way around Atlanta, but the traffic is usually less and your stress level may be lower as well. We stay overnight in Valdosta. Lots of nice places to spend the night before heading to Disney the next day.
I agree with this. Atlanta traffic is often just a parking lot, especially weekdays during rush hours.
From Dollywood, I would go north a few miles to Sevierville, TN and from there take
US 441 over to Knoxville, TN. Then
I-75 south to Atlanta.
Just south of Marietta, GA, take the Atlanta bypass (
I-285 -- either West or South, not East) to avoid as much of Atlanta as possible.
When you get near Macon, GA, look for the
I-475 bypass and take that to avoid the crowded, winding expressway through downtown.
Continue on I-75 to Valdosta and you'll find lots of hotels right alongside I-75. Valdosta is a little less than 500 miles from Pigeon Forge and should take you roughly 8 hours of driving.
There are also hotels in the Macon area, but some of the areas along I-75 there are not the best, and you'd have a longer drive the next day.
Stay one night in Valdosta.
The next day, continue south on I-75 into Florida. It's approximately 220 miles from Valdosta to WDW -- so about 4 hours. About 50 miles north of Orlando, at Wildwood, FL, I-75 will bear off to the right (SW). You will go
straight onto the
Florida Turnpike and follow that to the Orlando area. The Turnpike will bring you into the Orlando area west of downtown, and quite close to WDW. You'll probably exit onto I-4 westbound, depending on exactly where you are bound.
(It would probably be a good idea to stop somewhere in Florida before Wildwood and buy a Sunpass for the car. They sell a disposable Sunpass for $4.99, I believe and you get a $4.99 credit on your account, so it actually costs you nothing. You will set up your account with your credit card, and that will greatly simplify tolls and save you some money. Just be sure to remove the Sunpass from the car when you turn it in, so other drivers aren't charging their tolls to your credit card!)
I would also download Google Maps to your phone, and use it for navigation. Waze is another navigation app, but I much prefer Google Maps.
Have a great trip!