Windows 7: Problem with desktop interface

Hi, I recently re-installed my windows and encountered problem that i can't solve. So after windows installation when i install ATI catalyst drivers it seems that windows somehow do not change the look of taskbard tools and windows you open it just looks like without any display drivers installed. Also when u open a window and try to minimize it minimizes with noticible delay. So far i tryed installing diferent versions of drivers without any success. I hope u will have any clue of how to resolve this problem.