You will have to provide system information for anyone to advise more specifically.
Moving this discussion to the Premiere Elements forum.
Read display driver & Baddriver http://forums.adobe.com/thread/1327798
-AMD/ATI link in the above, Do NOT rely on Windows to tell you that you are up to date
-nVidia Driver Updates http://www.nvidia.com/Download/index.aspx?lang=en-us if you have nVidia
And, for the future, the information you need to give when you ask a question
-Premiere Elements FAQ http://forums.adobe.com/thread/1042180