I also think CloneDVD-to-PocketPC is a good idea! I have already tried different existing programs, but none of them worked too well.
I don't need it to be too complex... just compress the main movie is enough for me. No need for director's commentary, THX, etc. Just the main movie, and maybe subtitles also (for those noisy subway rides).
Typical file size would be 200-500mb (selectable) so that it can fit onto a memory card. The output format must be mpeg so that it is compabible with PocketPC's default Windows media player.