I have been having this flickering problem with menus of almost all applications, need help to solve

My laptop has this funny problem and such a flickering problem is not restricted to any one particular application or web browser such as IE or Firefox. Sometime the problem does not occur at all, but is back after a brief period. When this happens all Window screens behave in a strange fashion, and also the keyboard does not work or no keystroke works, I can only hear a sound similar to an error sound when I strike any key on the keyboard. Does any one know how to fix this?? Please help

I have been having this flickering problem with menus of almost all applications, need help to solve this plz?download windows xp

You should first check Viruses by antivirus softwares and then hardware problems can cause this problem ...