Just do a search here for Betaplayer and you'll find that lot's of people here have converted DVD's for Pocket PC use.
I could never get it right until this program called fairuse wizard came out. There's a freeware version that just simplifies the whole process. Again a search here will get you links to that program and links to a couple of user guides for it.
The Betaplayer Fairuse combo along with the X50v has made one of my original reasons for buying a Pocket PC come true.
And of course, Welcome to Aximsite!