It sounds like you've done a little homework already. Dollywood staff is usually pretty discrete about their guest "of size".
A lot of the bigger rides require guests to be 48" tall in order to ride, so you seem to be ruling them out up-front.
Blazin Fury shouldn't be an issue, Dare Devil Falls has no restraint system, Smoky River Rampage uses a velcro belt to restrain riders and they have "extenders" to accommodate larger riders, they're usually hanging on a peg on the posts near where you enter the raft, just grab one as you board, if they're not there, just ask an attendant. Mountain Slidewinder is a family ride where you're unrestrained, but there is a raft weight limit of 500 - 600 lbs (I can't recall the actual number). This is hugely fun to ride, but you will get soaked riding it, so dress appropriately.
As for the Country Fair area, many of those rides won't be an issue, Ferris Wheel, Scrambler, Bumper Cars, Swings (might be a tight fit, but should be ok) just to name a few, as well as the Train ride, which is just benches.