Hi,
I’m a bit of a newbie when it comes to divx or codec drivers(actually i dont know sh*t).. But what i do have on my pc is quite a few movies and the problem is i can only play say 70% of them... I’ve downloaded the latest divx player, tried using realoneplayer, winamp 3.0, windows media player, but i cant get more than sound out of some of these movies... What to do??? What to download? ?:( 
Try use the kazaa lite codec pack its the only worth while one getting.
here’s the link
http://home.hccnet.nl/h.edskes/finalbuilds.htm
hope thar help
Play one of the movies in windows media player, the right click on the filename, and press the first option, it will tell you what codec you need!
Hope this helps :)