I've recently been trying Gnome because it seemed like Compiz worked better under it than under KDE. Compiz has some nice features, like zooming (not resizing) a window to be full screen, that I really have been wanting to try. But Gnome has these icons on the root window which I don't need or want. I mentioned this to Mike and he gave me the recipe to disable it:

• Run gconf-editor (Applications -> System Tools -> Configuration Editor).
• Apps
• Nautilus
• Preferences
• Uncheck "show_desktop"