Thanks everybody for your help. I'll scan the web for VOBrator & VOBedit.
One of the reasons for wanting to convert a DVD into one long raw mpeg2 file, is so I can make a direct comparison with DivX and WinMedia9. --- Yes, I know, don't all scream at me at once 'Bill Gates Alert' But, I had to do it for a companies web site!
As we all know, there's no shortage of great programs out there to convert vobs or DVD's into DivX. I currently use DVD Decrypter, dvd2one (to reduce the vobs to a sensible working size) and MPEGMediator to create the finished DivX file.
However, initial trials with WinMedia9 Encoder have revealed that when encoding video at just 615kbps VBR (and audio at 64kbps VBR) the resulting 720x576 image is very watchable. And dare I say better than DivX. And I even bought a Sigma XCard to playback DivX on my TV.
I've also found that you can put a vob file (with 2 ch audio) straight into the WinMedia 9 Encoder and it will encode it. Although it's mind blowingly slow - 2 hours+ per GB. And this is with a 2.8Ghz P4!
Anyway, my next project is to find some software that will extract the 5.1 Ch audio from the vob file and generate 6 separate wav files.