To delete theme in Windows 7.
You can only delete themes in My_Themes which are unselected by right clicking on a theme and choosing 'Delete theme'.
How to remove my document folder from windows 7 Desk top
If you want to remove My Documents folder from your windows 7 desktop follow this procedure
Right-click Desktop, choose Personalize
Click "Change Desktop icons" in the left pane
untick user's files
Click OK.
To Set a Common Wallpapers in Windows 7
If you want to set a common desktop background for multiple users in windows 7 follow this procedure
you can implement this through Group Policy.
To set a common wallpaper:
User Configuration/Administrative Templates/Desktop/Desktop/Desktop Wallpaper.
(Specifies the desktop background ("wallpaper") displayed on all users' desktops)
To prevent users from changing the wallpaper:
User Configuration/Administrative Templates/Control Panel/Personalization/Prevent changing desktop background.
(Prevents users from adding or changing the background design ("Wallpaper") of the desktop
