One of my clients was using corel draw with an image, and after doing some things he can't exactly remember, he made the image he was working on the windows background.
Having him go in the windows desktop properties, Themes and Desktop both show the Windows Bliss Field and Sky background, and no mention of this image he was toying with in Corel at the time.
His normal desktop icons are overtop the image, so it must be a background. I think this system has an nvidia video card..Is it possible it has its own desktop background settings settable(?) outside of windows? I don't think so, but i've never actually cared to look.
I suppose it could be spyware related, but usually that sorta stuff doesn't pick corel files of choice
I bet this file is stored somewhere. A search and delete you think??