Display Color/Resolution Malfunction

Hello,

Just this morning I was working with Audacity, accidentally clicked the "play all tracks" and had 20 some tracks, many large and unedited... I instantly knew it was way too much for memory and tried to hit stop... Well, it wouldn't respond, started the color wheel spinnin and the fan to turn on to hyperspace, I tried to force quit, no response... the colors on the screen changed and got pixellated. It finnally allowed the force quit to open, and I got the program to stop. I restarted in an attempt to get the colors to go normal again...Nope, I double checked the display settings and reset them just to make sure, nope. Did a PRAM Reset... nope.

So here are the details... when I start up, the start up and log in screen are as beautiful as always, resolution crisp, colors smooth etc... then as soon as it loads the desktop, almost as if it is an overlay, the screen goes to heck. It looks like it switches on 256 color with the contrast blasted to over saturation.

Any ideas?

Many Thanks