I rarely get discoed but every once in a while I run into several in a row. It usually is telling me it's time to clean up my machine.
Run disc clean-up and delete everything in the recycle, temp and internet cache folders.
Open your web browser and delete all cookies.
Run virus and spyware scans.
Run the fast version of scan-disc.
Run disc defragmenter.
After this, turn off any and all auto-updaters in the start menu, and other non-vital programs.
While playing, don't run other applications. Allow your machine to dedicate itself to the game.
After all of this, if it hasn't helped, at least you know it's not on your end (but it usually is).