The first posts in the Multimedia forum will help you.
One tells you how to convert the dvd to a .avi file on your computer.
The other tells you how to encode the avi file to divx that makes it small(for me, a 2 hr. movie = 100 mb.)
A few notes
-all the software needed is free and there are links to all of it in the guides
-you will need a dvd rom in your computer to read the dvd and copy it to your pc
-the .avi file will be large (from 1 to 5 Gig) so you need a pretty good size hard drive but you can delete the avi file after encoding to divx so it is only temporary but if you dont have the space you will need another hard drive. (easy to check if you have enough free space, just go to my computer, right click on your hard drive, and select properties)
-also make sure you have a cf or sd card big enough to hold the end divx file. so you can play it on your ax
-the encoding process takes a while and you shouldnt use your computer while you are encoding.(i usually encode at night so it dosent tie up my computer in the day time.)
-For me the i didnt have the same version of divx so I just didnt touch the divx settings(this is just a tip if you decide to encode using the guides and you cant figure out the divx instructions)
-I encode in stereo because i use headphones, in the guide he encodes in mono so jsut select stereo instead of mono when it comes up if you are going to be using headphones
-Hope this helps and hope you get your movie on your ax