Recently I moved into a college dorm and brought with me a router (so I could plug both of my desktops into it - don't ask me why I brought two, I am just crazy). Anyway, I can use the internet fine and I can use my own network fine (the network my router creates for me). The problem occurs when I try to use the college network. For example, if I host an Unreal Tournament 2040 server and my friend down the hall attempts to connect to it (via LAN), he is unable to see the sever in the LAN, but if he connects it via my IP, he can connect to it perfectly fine. I have already attemptd disabling NAT (this made it so I couldn't even go online). I have also set my subnet to my college's subnet (for some reason, they are using 255.255.255.128), and I have even tried static IPs - nothing seems to work, so far. Any help is greatly appreciated.

but if he connects it via my IP, he can connect to it perfectly fine. That kind of answers your questions doesn't it. If he can connect that way, return your router setup to what it was, and have him connect by your IP address.

That's my current setup. I'd like it to be able to have it so my server is visible via the LAN if possible...

I am by far not a gaming expert, but your post confuses me. If you have a NAT router connected to a drop in your dorm room, and you have two desktop computers connected to an integrated switch in this router, neither of those computers should be seen via My Network Places or Network Neighborhood. This is assuming that you have NAT enabled on the router. The only way that your PC's behind your NAT router can be seen on the LAN would be if you forwarded all of Microsoft's NetBIOS ports to the internal IP of your machine that is hosting the game. Is your college allocating public IP's to students in the dorms? If you want to keep NAT enabled, have your server visiable via the LAN, and host the game you are going to have to setup some port forwarding on the router. You will have to forward NetBIOS ports as well as the ports that your game uses.