PC
Click on the link below that matches your desktop size. The wallpaper will appear in your browser, then right-click the image and select "SET AS WALLPAPER."

MAC
Click on the link below that matches your desktop size. The wallpaper will appear in your browser. You will need to save the image to your hard drive (click and hold the mouse button on the picture and choose "save picture as..." from the menu that appears.) Control-click anywhere on the desktop (not an icon) to bring up the sub-menu, select change desktop background, select the picture tab. Click select picture select the image you saved and then click set desktop.

HOW DO I USE AN MSN ICON?
Right click on your choice of icon and click "save picture as". When the dialog box appears, browse to the folder where you want to store this image. Click OK. Open MSN Messenger, then import your display picture.