This issue started a few days ago but it has progressed to the point where I can no longer operate my computer. While playing a video, the video's picture would freeze, change (in that it would suddenly become highly pixelated and the colors would change strangely) and the sound would slow WAY down and stutter. The entire display would then be completely unresponsive, forcing me to turn it off via holding the power button down.

When I would subsequently turn it back on, it would not display normally. Instead, it would start out completely white or gray, then slowly fade into either black with vertical red stripes or total white. From there it would fade into white or black, respectively (sometimes blue like the login screen). There would be a solid vertical black bar between the webcam lens and the right rubber nub (my right). Also, along the edges of the screen, it would gradually become white in a texture that looks like the spray paint tool in MS Paint (note that this detail is not dynamic; it is like that from the moment I turn it on and does not change). A few restarts would cause the display to revert to normal as of a few days ago, but as of today, nothing will fix it. 

I've been having other issues with frequent BSODs lately, all occurring while watching videos.

I believe it might be an issue with the hardware due to the fact that I can still operate the computer to an extent. I can log in by typing in my password and hitting Enter, and I can hear all the sounds of my programs starting up, such as the Skype yawn. Also, after logging in, the display would fade to black (if it wasn't black already).

I'd be extremely grateful if anyone could point me in the right direction. This computer is my livelihood and what I do all my schoolwork on.

Misc. technical information:

Windows 7 Home Premium
4GB DDR2 SRAM
NVIDIA GeForce 8400M GS