Your tenacity compels me to help though I am tempted to just send you the link to the torrent so you can just download the soundtrack and be done with it. I'll refrain for obvious reasons.
Follow these instructions.
First install 'mountiso' through Synaptic. Then reboot.
Then go to the directory where the .iso is located (/home/alex/DVD/Shins New Slang/sonata_volume.iso)
Right click on the .iso file (not the .idx file).
Upon right clicking you will see 'Manage ISO'
Scroll down to it then click Mount Image.
A dialog will pop up asking for your root password. Enter it then click 'OK'.
Now you will see 2 folders. Enter the folder that is named VIDEO_TS
Now you are in the VIDEO_TS folder.
At the top of Konqueror click 'Settings' then click 'Show Terminal Emulator'
A black box will pop up at the bottom of your screen.
Type all the VOB files in numerical order. Below I've given you an example but don't just copy and paste my example. You will have to type them one by one (remember only the VOB files in numercal order) from beginning to end. Remember to start by typing cat
then your VOB files in numerical order and end it with > ShinsNewSlang.mpg
It will look something like this:
cat VTS_01_0.VOB VTS_01_1 VTS.VOB _02_0.VOB VTS_02_1.VOB VTS_03_0.VOB VTS_03_1.VOB VTS_03_02.VOB VTS_03_03.VOB > ShinsNewSlang.mpg
After you have typed it all out exactly as I explained hit enter on your keyboard. Wait for the file 'ShinsNewSlang.mpg' to be completely created (you'll see it while it's being created but wait for it to finish). It will take a while so go have a drink or something. Then after it's completed creating ShinsNewSlang.mpg' (do not touch it until it's completed). Then you can use audiokonverter as I mentioned before.http://www.pclinuxos.com/forum/index.php/topic,73826.msg609009.html#msg609009
After you have finished remember to move whatever you want to keep (the newly created MP3 for example) to a more permanent location like /home/alex/Music or wherever.