We spent a week in Nashville last spring. It was a good time and thee is tons of stuff to do. If you run out of major attracktions just hit Broadway and sit in the bars. There are some of the most talented people the rest of the world will never know. My favorite was Honky Tonk Central. There are 3 floors and there was a live band on each floor. If you get down to the bars for music track down a gentleman by the name of Brit stokes. If you can find him in one doing his solo acoustic show you will just be blown away.
A short drive south will get you to Chattanooga as well. If you get down there you have to check out the Tennessee aquarium. It is one of the best I have ever been to.