Windows 7 - No video, just audio...help

I recently installed windows 7 64 bit and all my drivers were restored perfetly, i had done a back up from my vista, and my graphics card is mobile intel (R) 4 series express chipset family and in the device manager it says it is working perfectly....but when i play a video (avi) file in vlc player..it is version 1.01 i just hear audio but no video, its a blank screen and the windows color scheme changes from the aero to windows 7 basic color scheme, what could be the problem? and when i use WMP the same thing, just audio and no video....
And i use a toshiba L300
Thanks in advance...

This could be nothing more than a codec problem, but without any system specs its hard to tell...Please take the time to fill them out ... click on the link in my sig....

Shark007.net - Windows 7 Codecs

I downloaded K-Lite codec and windows classic media player and it was just a codec problem and now the video files open..phew..thank for the help..