Hi all i have a problem with my pc and i think it is due to a direct x driver, i had the same problem earlier so i installed DirectX 9.0 SDK Update - (April 2005) and DirectX 9.0 SDK Update - (June 2005) which i installed from the microsoft website without any problems. Since i only had 5% free space i uninstalled those two drivers without thinking, now when i go to the microsoft website it asks to validate my windows, so thats fine until it says that it cannot validate windows because i have problems with my internet connection, i know thats not true otherwise i wouldn't be able to post this topic. If i didn't need my P.C for work i would have smashed it up by now.
can't be 100% certain it would work, but you could try, uninstalling any programs or utilities you never use, back up (if possible) any music/video etc, and download this utility click here and run it immediately, and let it fix all selected problems.
Next, you will have to run a full disk scan, and defrag, before reinstalling directX9.
This may work, and get your system running again, but it will not run at the speed it could.