ABC said:

Moth3r said:

The easiest way would be to use DVD Decrypter in IFO mode, with stream processing enabled, to extract the audio track you need.

Indeed, easy to do... But that's where I'm entering a new world that is all what I'd liked to avoid... I expected to have directly a AC3 or PCM file...

You should have ended up with an AC3 file or a WAV file. Did you click the "stream processing" tab?

You can use something like azid or besweet to decode/split an AC3 file into mono WAV files for each channel.