Ah - good choice - this is one of my favourites! I suppose you what to know how to get it on the desktop now. There are more that one way to skin a cat when it comes to setting the wallpaper / bcakground as your desktop. One way is to right click the desktop background below and then choose 'save target as...' (IE & Opera) or 'save link as...' (Firefox). Don't forget where you saved it though! Next goto your computers display control panel and set the background to the image you just saved.
Another way is when the full screen wallpaper is shown, right click it and select 'save image as...' or 'set as Desktop Background' or 'Set as Background'. You will understand what needs to be done the the moment arrives.A walk in the park for you. I reckon you know already.I'll button it now.
Return to wallpaper thumbnails.