Dollywood is great! Is it Disney, no, but it's about a hundred times better than Six Flags. There are a lot of fun attractions, but also a lot of "relax and take your time" sort of things to do.
Weekdays are usually dead, but even on weekends, the crowds are not too bad, especially if you get there early. Hit the big rides first. There are 3 big popular roller coasters - Thunderhead (wooden coaster - FUN!), Mystery Mine, and Tennessee Tornado. The water rides get longer lines in the summer, and they are my favorites! Blazing Fury, Slidewinder, Daredevil Falls, River Battle, and River Rampage. DO bring a change of clothes/socks/underwear, because you will get drenched on many of these rides!
The shows are all pretty good. I believe that the show schedule is on the Dollywood website, but it does change from week to week. You can also pick up a schedule when you enter the park. There are usually one or two outdoor bluegrass-band type shows, which are worth checking out if you like that kind of music. The stage shows are OK - not my favorite. There is a bird show which is pretty cool (Dollywood has an eagle sanctuary). Even if you don't see the bird show, check out the eagle sanctuary. It's great to spend a while watching the eagles and birds.
There is also a country fair and 50's themed area, which is where most of the kid's rides are. The 50's area is cute, and there is sometimes a 5-person acappella doo-wop group that sings. They are awesome if you manage to catch them!
The park is large, spread out, and extremely hilly - bring comfy shoes!
The people-watching tends to be excellent at Dollywood, if you like that sort of thing.

There are a lot of neat shops that deserve some browsing time.
As for food - YUMMM - stay away from burgers an

d fries. Get barbecue, or skillet sandwiches (they cook either shaved steak or bratwursts, onions, and peppers in a huge cast-iron skillet), or flatbread sandwiches (they cook chicken, onions, peppers in another huge skillet). Basically, any food cooked in a giant skillet is awesome.

There is a homemade ice cream place where they churn it themselves and it is really good.
There are a lot of discounts available locally -
AAA, coupons at local grocery stores or fast food places (Wendy's, etc)., so it is worth checking around before you go. A local grocery store, Food City, sells season passes during the off-season for really cheap, if you think you might want to do more than one day.