Audicity not recognizing sound?

I’m sure this is a file issue, I downloaded a DVD from a p2p sharing site. It came in like this, ISO File (.iso) And wouldn’t open however after screwing around with things I found that VLC would open it no problem. Good video and audio. Then I dropped it into AVIDemux and also ANY Video Converter thinking I would separate the videos contained in the file. They didn’t recognize any sound. That lead me to, wait for it, Audacity. How can I retreive the sound from the .iso file with Audacity. Is there a plug in or codex I need to add?? My version is 2.0.3

Audacity does not directly support ISO disk images. Try IsoBuster.