1) Don't post in more than one section. Your question is clearly a website design question so posting in Programming will do you little good.
2) Caps lock again. It's the little key on your keyboard that says.. wait for it.. Caps Lock.
3) It helps us help you when you give a descriptive subject header other than HELP.
4) Just who is MR ASAP and what is his question?
Now that I have that out of my system, are you asking how you can use the visitors wallpaper as your website background? Or are you asking how you can change the visitors wallpaper via your website?