well best thing to do would be to get a Behringer U-Control, as you can just play the DVD, get audacity then record the dvd playing the audio into your pc straight
__________________
Fender American Deluxe Strat
Ibanez S470
Line 6 Spider III
I wonder if you could use Windows Movie maker. I know it separates the audio and video channels for editing. If able to open the file in Movie Maker, you'd just copy the audio and create a new file and paste in the audio track. I've never tried so, I don't know if it would work.