We live here in Nashville and my office was literally a short walk from Two Rivers Campground for several years. Someone mentioned in an earlier post to check out rvparkreviews.com which is an excellent suggestion - we use that resource a LOT in hunting potential camping sites. Anyway, Two Rivers Campground and Jellystone Park are both very nice, very well maintained, and very convenient. A KOA sits a bit farther down the road, and it's also nice, but seems to stay less occupied that the others, I'm guessing because of of the always-premium cost you find at KOA's.
Very close by is the Grand Ole Opry House, where the Opry returns after a winter at the Ryman Auditorium downtown. Cock of the Walk is a great restaurant (fried catfish, hush puppies, fries, fried pickles, fried......) seriously it's very good, but you'll get your grease quotient for the day. Logan's Steakhouse just built a brand new restaurant very close by and it's great. We eat there once a week.
If you need any more tips or info on Nashville, give me shout. We are in the music business so we know the spots see hear great live music, if that's of interest to you.