First off, forget about divx 4 for now... It's not as good as 311a, which is what everyone uses.
There are many steps to creating divx. If you have some free time and are serious about it contact me from some way (in my sig) and I can help you via netmeeting or just good ol chat.
I have all of the programs you'll need if you contact me.
BTW, you will need a DVD player if you want to rip DVD obviously, and a semi fast processor (the faster, the quicker it will be, for me at 950MHz, it takes 3.5-6 hours purely dependant on length of film).
Hope to hear from you, I've been extremely bored lately!!