Sorry I didn't see this post sooner...
A desktop is just a canvas, it may simply be a black background. You said you do see the icons. Are you saying you can't go to any of the corners and locate a Start Orb?
What happens if you boot normally? Why do you assume it has a virus? Boot normally then try right-clicking and choose personalize - choose another theme.
If you can get to a point where you can run a program, you can install the product SIW and it can tell you the product key. A link to this is available in our
Freeware DB.
Side Note: If the windows is not authentic the system will set the background to black by default and you should see a not genuine message in the lower right. I don't think this is the posters situation but I mention it for others who may find this during a search.