Pay more attention to the mood you want to create than worrying about a particular genre. If the main activity is expected to be conversation, pick something upbeat, but not too rocking or distracting. I find Dave Mattews perfect for this. Mellow enough to be able to talk over, intersting enough to listen to if someone gets bored with the conversation, jazzy enough to sound sophisticated, and generally upbeat and happy.
Also, NEVER LET THE MUSIC STOP!! I'v seen several times when the music stops and people start leaving before the host can put another disc in. It struck me as strange. Even if they don't leave, they will feel the change in mood, and feellet down (if you chose well), or relieved (if you chose poorly or played too loudly). You really want to keep the volume down very low.
Also, NEVER LET THE MUSIC STOP!! I'v seen several times when the music stops and people start leaving before the host can put another disc in. It struck me as strange. Even if they don't leave, they will feel the change in mood, and feellet down (if you chose well), or relieved (if you chose poorly or played too loudly). You really want to keep the volume down very low.