Bandwidth Monitor

[Spyrus]

I have been having a strange issue recently at home. I am hoping to do some analysis but dont have a lot of experience in investigating network traffic/packets...

One of many issues:
I have some roommates that rent from me in my house and use various amounts of bandwidth for whatever.

I am an avid gamer as is one of my other roommates but whenever we both get online and play something like halo 3 we end up killing the network connection. In order to fix this issue I have to reboot the router and cable modem wait and then it will work again for x amount of time before we kill it again. Its getting quite annoying.

Background Info:

Network setup:

WAN>Linksys Cable Modem> Linksys WRTG54g wireless Router>Some PC's
                                       |-------->Cisco 2624 Switch>PC's,Xbox

I cant remember if the switch is connected with a crossover or a straight thru cable, not sure if that matters.

Now I currently have the Xbox port forced to 100/full on the switch and dont really see a setting for that in the xbox, this could be part of the issue. I dont have any VLAN's setup on the switch either, everything is currently defaulting to VLAN 1 as I have never had to setup VLAN's before so I dont know how to segment it. I will probably do that soon to isolate game stations vs my PC and then my roommates PC's so I can keep them away from my ****.

Goal:
I would like to be able to see why the internet is crashing, overload? bad packets? not sure what might be happening. I would like to make sure bandwidth to each node is controllable. I would like to do any other cool things that might force me to learn something about my network.

I have an extra PC that I was testing Ubuntu on so I have a PC I can dedicate to this if I need to set it up as a box, ideally i would like to use this box to run a firewall between my modem and router but thats open to discussion and can be compelted after I troubleshoot my current issue.

Any help would be appreciated.