I just had to reinstall Windows due to a nice crash

After I did this, I got a few windows updates incl. SP2 and installed my mouse, then I played DAoC (seperate partion) with no problems at all.
Later I got rest of windows updates and installed my mail backup program, my anti virus and firewall, firefox and winamp, closed computer and saw a movie, came back and wanted to play only to find out I could just enter the game and if lucky play 5 min before it crash, anybody got a solution to what could be wrong???
And I have DirectX 9.0c so it got nothing to do with that.
I can play all other games I got (single and multi) without problems, so are a bit lost.