Careful with this one - can be slippery when wet. I suppose you what to know how to get it on the desktop now. Getting the wallpaper onto your desktop background 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 goto where you set the desktop background for your particular computers operating system and select the image from the location where you saved it.
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'. When you're ready - you'll know what to do. A walk in the park for you. You probably already know in fact. I'll zip it for now.
Return to wallpaper thumbnails.