File sharing and Linksys router

[SoUp]

I currently use a Linksys router to connect two computers to a campus network. I can't access any computers on the LAN (computers outside my router but still on the campus network). I've tried to open the ports for file sharing and also tried using DMZ Host but I still can't access any of them. I'm running Windows XP and I have Client for Microsoft Networks and File and Printer sharing enabled. What could be the problem?

 

[JackMDS]

LAN ? 1 is your two computers.
LAN ? 2 is the Campus.

Congratulation your are on a WAN.

Better, ask the campus IT how to do it.