To perform settings, your account needs to have administrator rights.

On the desktop locate the icon named "My computer", mark it with the mouse and press the right mouse button and activate the menu item "Properties". In the opened window Windows XP enter in the "Advanced" tab. In Windows 7 you need to click on the link "advanced system settings", in the opened window go to the tab "Advanced". Further, in "Performance" click "Settings".

Go to the tab "Visual effects" click "adjust for best performance". On the Advanced tab, put the switch "to Optimize the performance of: programs". Then click OK in the two Windows respectively.

The result will disable many visual effects in Windows and the appearance of the desktop. This will significantly increase the speed of opening of Windows and reduce the load on the graphics card and RAM. And you don't have to reinstall the operating system.