iBook G4 cannot connect to the Internet AT ALL!

I'm a college student with an iBook G4 and I live on campus during the school year. When I'm at home, I can connect to the internet just fine. Anywhere I go, I don't have a problem. But starting this year, I cannot connect to the Internet on campus. I live in the on-campus apartments and I cannot connect to the residential network there using ethernet. We have a wireless router in our apartment and that won't work for me either. At best, I can sign into the residential network using my school account and I can get on one or two websites before "Safari cannot find server".

There are also two wireless networks on campus, one called "Campus" and the other "Visitor". You have to sign into your school account to get on Campus (like you do for the residential network), but you don't for Visitor. I can get on Visitor fine, though it's quite slow and I can't use iChat.

What's even more frustrating is that there are many other people with the same exact type of computer as me, and they work fine. I've taken it to the Office of Information Technology (the people who run the internet on campus) and they can't seem to figure out the problem and are content to ignore me. So now I'm paying with my tuition for a service that I can't use! Does anyone have at least an idea of what could be happening? I think I covered everything, but if you think I'm missing something, let me know. Anything that helps solve this incredibly annoying problem!