Black xp window

Hi
I changed my display setting on xp window and by mistak selected multidesktop .
And the icons disappeared and I found that they are hiddin on the right side of the desktop which i can see. If I open any page it goes towards right side my my desktop and I cannot see it. I managed to open control panel and display setting on desktop which I could see but after changing setting the screen went black and I can do nothing. Please help I have to submit project .