Here is a small and simple program called Starter Background Changer that enables ‘Personalize’ option in Windows 7 Starter edition as in other editions of Windows 7 and let you change your wallpaper.
The program has the following features:
– Looks similar to other editions of Windows 7 Personalize option
– Supports PNG, JPG and BMP images.
– Option to change the position of the picture (center, mosaic, stretch, filling, normal)
– No taskbar or other icons