Automatic mouse right click in windows vista

This hapenned a while ago. I am using a wireless mouse and it was working fine for over a month. suddenly automatic right click menu started popping up everywhere. I mean internet explorer, desktop, explorer window everywhere. I have tried every option that I found in google like updating the mouse driver, system restore etc but nothing worked. It happens all of a sudden, sometimes many times in a row. I even disconnected the mouse and uninstalled the touchpad driver but still its popping up. I scanned my PC for virus with Microsoft Security essentials but did not find any virus. Could anyone pls help?

Thanks in advance!