If you have a version of Windows other than Windows 7 Basic, and your screen changed from Aero transparent desktop to Basic setting, then you might want to return to the Aero transparent look.

Click the Start button and type “aero” in the search box.  Click on the search result that says “Enable or disable transparent glass on windows.”  Run the troubleshooter which will ordinarily fix the problem and advise you that “Windows desktop manager is disabled” or that “Windows desktop manager is not enabled.”  Desktop manager must be enabled in order to enable transparency.  You will notice whether the task bar is somewhat transparent (aero effect) rather than solid (basic).