Locking down desktop settings in XP

I am in charge of regulating background images inside of XP Professional. How is the best way to lock down the settings from normal users? Is there a group policy (W2K server) that will allow me to do this? We also would like to have a custom logo be their background, but these are remote computers that we will never “touch”- the vendor is imaging and sending the pc’s. if anybody could help, I could use it!