Most likely, it is the video driver that is corrupted. I would go to their website and download the latest driver for that video adapter, then reboot in safe mode, uninstall and then reinstall the driver. Also, make sure the laptop is well vented/cooled during operation.
Thank you for responding. I am not too savvy about these things and I don't really know where to start to identify the "video adapter driver" in order to reinstall it. Since it is my everyday cursor that developes this rectangle, does this mean that some video component is corrupted and interfering with the everyday laptop functions? My laptop IS called an "Entertainment Notebook" but I didn't buy it to for that purpose, really. THank you again, Anne z-d