After being used to AutoGk for ages, and its temperamental behavior, it was a great relief to find StaxRip - from the website :
"With StaxRip you can easily convert your DVD's, DVB captures and many more formats into MPEG-4"
Just tried it last night, managed to compress Ice Age from 3 VOB files to a 1GB AVI file, including the AC3 soundtrack, and the quality looks fine(certainly good enough for kids movies)The one pass mode seemed to work in almost real time... I didn't time it exactly, but usually these things take an age - good stuff
Thanks for the recommendation uknova!