Pointer

I didn't read the entire thread but instead of going back to windows, why not put your computer in front of the router. That way you can use Linux's Server capabilities and turn it into a router. Once the connection comes directly into your linux box, it can then go from there to the Router (Of course you'll need 2 network cards) and from the router to the rest of your network. There are plenty of network monitoring tools out there for linux that should suffice what you are looking for. If you want to stick with windows reply to this for another answer.

not to be rude but if u read u would find that the most complicated program I have ran on my linux box is solitare, but that router os that runs off a floppy would be fun to play with.

that sounds like what I need

With DMZ enabled does all the traffic go to the other computers that it was destined for also?
please post in actual question because there are 2 people convinced that what I need is impossible with my router or extremely difficult If i use a managed switch.

THen I can Give u points in both questions

With DMZ enabled it sends ALL INCOMING traffic to only 1 computer. You can change the setting to another ip address but once again it only sends the incoming traffic to the "1" system you specify on all ports. (This does not affect normal internet browsing for the rest of the computers on the network)

I wouldn't use that switch to try what you are doing, you could still put it on the network just don't block anything or you could disable the DMZ from the switch side.