Early 2008 Macbook Pro-Distortion when scrolling through windows

[jmks]

My Macbook Pro starting showing some visual tearing/distortion when scrolling through windows or even watching a movie. It's like there's an invisible horizontal line across the screen that distorts the picture. I have also noticed that the line doesn't stay in one spot, it moves from the top to the bottom of the screen over and over again. I had some issues with the monitor within the first month of purchase in July 2008 and they have to replace some of the LEDS in the monitor...and another unrelated issue in Dec 2008 when I turned on my computer to find that the hard drive had completely blown itself up. Anyways, that's a bit off topic...any suggestions? THanks!