Ah - good choice - this is one of my favourites! I suppose you what to know how to get it on the desktop now. You can set the wallpaper as you desktop in a number of different ways. You can either right click desktop wallpaper beow and then select 'save target as...' (IE & Opera) or 'save link as...' (Firefox). If this is your chosen route, remember where you save it! Next you need to go to where your computer's operating system display settings and set the image as your background / wallpaper.
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'. When the time comes - you'll know what to do. I trust you. You know already I'm sure. I'll shut it now then.
Return to wallpaper thumbnails.