Are you look for straight forward bar or do you want live music? Also, what part of town are you in?
Barbecue, I recommend Mickey Roos BBQ in Franklin. Its Texas-style and we have held our Muster there the last three years. They take good care of us. I also like Famous Daves, if you want something a little more chain-restaurant-y.
As for bars, personal favorite for just straightforward bar is Riverfront Tavern on the corner of Church and 1st downtown. Make sure you check out our Yazoo Brewery. Their new taproom rocks... we just had Aggie Happy Hour there and they had to run us out.

Live music, you have your pick. Personal favorites are The Stage, Second Fiddle and Legends. I personally avoid the purple trap, aka Tootsies. Too packed, too hot, too touristy.
Sept. 8 & 22! We have an Aggie doing showcases from 8 - 10 pm at the Fiddle & Steel Guitar Bar in Printer's Alley. COME ON OUT! I'm going to try to get a few Aggies out one or both of those nights, so feel free to come say Hi! (Also, Fiddle & Steel is my home away from home. Tell 'em I sent you. LOL!)
If you're going to be more around Franklin or Belmont or Vandy areas, let me know. I can throw you some recommendations for those areas as well.