Downloading Images: Click on the small image, and the full version will be downloaded and displayed. It is then just a matter of using your internet browser to save the image.

Setting an image as desktop wallpaper: Use one of two methods. The first is to click the right mouse button on the downloaded image and select the "Set as Wallpaper" option instead of "Save Picture As". The second is to use the Windows Control Panel, and in the Display Control Panel set the background to the image downloaded.