How can I change the preferences on this computer?

[archcommus]

So there is this old computer in my study hall in school that I use daily to visit websites and stuff. It's a PII 233 with 64 MB of memory. Since it's on the school's network you have to use your network name and password provided by the school to log on. The theme is very ugly and it has tons of crap on startup, but no matter how much I try to change the theme/startup apps, it resets to the SAME ugly theme and the same list of startup apps when the computer's rebooted. Are these all being controlled by the network then?

 

[quakefiend420]

probably

 

[archcommus]

I can't imagine something like the wallpaper on a computer being unoverridable.