Windows 7 Change Login Wallpaper
First youll make a Registry edit that enabled custom backgrounds and then youll store the image you want in a special Windows folder.
Windows 7 change login wallpaper. Enable Custom Backgrounds in Windows 7. Set a Custom Login Background. Windows 7 Users.
If you want to remove it simply delete the picture from the backgrounds folder that you created and the default blue login wallpaper.
Source : pinterest.com