If you're using Headac3he, then you can use 128kbps and it will still sound very very good. This will save you a lot of room for your video file so your kvcd will look much better. You could even go as low as 112kbps with the audio and it will still sound pretty good (it's acceptable, but I usually try to use 128kbps when possible, and I think that's probably what
most people do here for most of their movies). Try 128 or 112 and see if you like them or can hear the difference between the them.
If you are encoding a concert DVD or other type of music-related dvd, you may want to use higher audio bitrates though like 192kbps or 224kbps. It depends on what is more important to you....video or audio.
-d&c