Not sure if you're problem has been resolved or what. But, to get any kind of community (the free kind) support over here - you're going to have to be a little more specific with your issue.
The problem you describe above, could be a gazillion different things. Do you have issues with any other visualizations/graphical applications? What kind of video card ya' got? Current drivers installed? Is your machine running great in all respect, except for this? etc. etc. All we know, is you have WinXP...