I would like to setup a default desktop background & get it out to all of the machines.

So I setup a user configuration to modify the registry:

 

The wallpaper is changing but the image needs to be centered.  I've tried all 3 "wallpaperstyle" settings (0,1,2) and the image won't display properly.  I need to have it set to "fit" so that the full image is displayed. 

 

I have a mix of Win 7 & Win XP.  What is the best way to configure this so that it ensures the default background is set each logon (mgmt requirement unfortunatly).