and if not installed:
ac3/acm decompressor: from here
and lame mp3: from here
unpack the AC3ACM, right-click the AC3ACM.inf, you'll see the option "install", confirm
unpack the lame mp3, right-click the LameACM.inf and "install"
************
Run VDMod and locate the dvd-video you want to rip/convert audio from
(I had the files saved on my hdd)
use the "mark in" and "mark out" to select the part of the video you want

video --> full processing mode --> compression

(will be using the xvid codec)
configure:
profile level --> unrestricted, encoding type --> single pass, target bitrate --> I'll go with 700 (you can go higher if you like)

quality preset: "user defined" and click "more"
motion search: 6, VHQ: wide search

left the other options as they were and OK.
To change the screen size: Video --> filters --> add --> resize
and pick the desired resolution

Go to stream --> stream list
right-click the audio stream and "full processing mode" and "compression"
select LameMp3, 48,000Hz, 320kbps CBR, stereo and OK

File --> save as and choose a save location and save name
you get an avi file clip with mp3 at 320
to get the audio from there:
load the avi in VDMod
streams --> stream list --> pick the audio and hit "demux"

you'll get the mp3 at 320
*total time taken: 3 minutes
repeat if you want more clips from the same video source
and that's it :)