One last notation -
There are several discussion threads about how to set up a Guest Account with your own preferences, such as here:
http://discussions.apple.com/thread.jspa?messageID=6578902
I think it is far easier to set up a Standard User account, and then customize it the way you want by logging into the account and changing any Desktop Wallpaper and Icon settings, THEN logging out, and then logging into your Administrator account.
Then, when you go to System Preferences and choose "Parental Controls" (NOT the one found under "Accounts"), you can choose special options such as "Use Simple Finder" and turn off "can administer printers", "can burn CDs and DVDs", and "can change password". You can even limit what applications they can use.
If you want to know more about Simple Finder go to your Help menu in the Finder and type "Simple Finder" Choose the Apple help article entitled "Setting up a simple interface for an account".
After I set up my Standard account I tried to apply an icon to the Home Folder while I was logged in as an Administrator. Interestingly, I was not able to do so. But when I logged into the Standard Account I just made, I was able to apply the icon to the Standard User's Home Folder.
So now all my icons and User Accounts are set up perfectly. Now I will make a disc image back up of the hard drive, and then on to updating to OS X 10.5.7.
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