Careful with this one - can be slippery when wet. Do you need to know how to put this on your desktop? Setting the background as your desktop wallpaper can be done in a number of ways. You can either right click background wallpaper below and then click 'save target as...' (IE & Opera) or 'save link as...' (Firefox). Please remember where you save it to!Now go to wherever it is you normally set your desktop backgrounds for your computer and selected the saved wallpaper.
A different way altogether is to right click the background below, from here choose 'save image as...' or 'set as Desktop Background' or 'Set as Background'. When the time comes - you'll know what to do. A walk in the park for you. My guess is you already know. I'll keep a lid on it now.
Return to wallpaper thumbnails.