I'm pretty sure that it has something to do with the setting. I just got a used router from gamestop. It has 4 ports. I hooked up my xbox, now I want i want to do a second computer. I thought that when I hooked it up that it would straight go online, but it didn't is there some settings I have to changed......I'm a networking retard so bear with me

Ok - I think it has to do with the fact that your network only has one TCP/IP address and so you are trying to run two devices on the same Ip. To get around this you need another NIC (network card) the first from broadband etc., the second goes into the uplink port on the hub (port 1 or 4?!) and then Xbox is given an address from the 1st PC ...
I've found a site with info (balm pot who wrote it) but it has the info...
http://homepage.ntlworld.com/section-31/projects/index.htm

Have fun!