Do you have the broadband account already set up at your apartment? It's usually pretty straightforward if you do. Just plug the broadband into the router, and the router goes to the PC(s). Or into the hub if you have one. Windows XP usually autoconfigures your Internet settings if you plug into a router.
You probably need to "activate" the router through the IP address given for it at your apartment. I'd dig through the router instructions; it should give you an IP to go to in order to "start it up."
Sorry for the vague instructions, but there's not a whole lot you can do unless we know every little detail about it.
You can always call the ISP and router manufacturer...that's how I solve some problems with my router. One last ditch effort is to make sure DHCP is enabled on your PC. Good luck!
-Lasereth