my desktop is blank except on reboot for several seconds

I don't know what it is that i clicked on however my desktop is no longer avaialble to the naked eye. I can't see any of my icons or pictures or anything. I can see it for a little while, like ten seconds after a reboot but then it goes black. I can still get onto the net via the button in the lower left corner but thats it. can anyone help?

Hi,
please read THIS post, and post your HijackThis log file in this topic.

Wait for instructions given only by DragonMaster Jay, Origin or Belahzur