My guess is that your desktop is trying to display web content.
On Display Properties, under the "Desktop" tab, click on the "Customize Desktop..." button. Then click on the "Web" tab and make sure there are no web pages checked.
Hope this helps.
I made a mistake the other day and downloaded a supposed to be spyware after I was told I had a virus, now after I unistalled it I have no wallpaper. I have gone into the display and tried change it back to my wallpaper and I thought it was the dreaded blue screen, but I can change the color and when I sign off the blue screen disappear and my wallpaper is there. When I was under the display panel everything was grey out.
HP win XP

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