I was surfin the net, suddenly my monitor went black as if I restarted the PC. I turned it on and off, the screen appeared white then turns black later on. I restarted the PC but the color display became yellowish, and the colors doesn't appear the right one.
Can someone tell me why the monitor all of a sudden went black. And why the color display are not working properly.
I've tried the appearance settings and monitor adjustments but still don't work...

Sounds like the monitor may be on its last legs. If you have another monitor, swap them out and see if the other performs fine. If it does then replace the dying monitor. If it experiences the same problems then its with your video adapter and that probably needs replacing.

If it's a CRT monitor than the gas/bulb might have run out. The only thing to do now is to get a new Monitor preferably LCD...