What a peach of a wallpaper don't you think? I suppose you what to know how to get it on the desktop now. Setting the background as your desktop wallpaper can be done in a number of ways. You can either right click the background below and then choose 'save target as...' (IE & Opera) or 'save link as...' (Firefox). If you do this - remember where you saved 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 has loaded, right click it and choose 'save image as...' or 'set as Desktop Background' or 'Set as Background'. You'll know what to do when the time comes. I trust you. I bet you've figured it out already. I'll keep a lid on it now.
Return to wallpaper thumbnails.