or, use winDVD instead of WMP
Also go to DIVX.com and DL their latest drivers and player but keep your WMP as default if you want, but DIVX will give you the needed plugins for a lot of things u want to play and if u can't open your "PORN" with WMP then the DIVX player will do it for you :P
Also, try using VLC
http://www.vlcmediaplayerweb.info/us/