[zebra 23121] Zebra a good fix for gaming issues?

Sorry if this message is a double post, I am new to the whole mailing 
list idea and missed a couple steps in subscribing before sending.

Hello All,

I'm having an issue with one of my games.  The issue is that the game 
(Battlefield 2142) uses so many ports, that it interferes with everyone 
else on my network because all those ports have to be forwarded to my 
machine, and if I don't have the ports forwarded, I can't connect to any 
of the game servers.

Anyways, what I'm trying to do is to get a cheap, yet effective solution 
to this issue.  I don't have the money to go out and buy a new hardware 
router, especially not to get it home and find that it does no better 
with this issue.  I've heard that the issue is more that my router is 
too simple, and that to resolve this issue, I'd be better of getting a 
new (probably very expensive) router capable of doing very complex routing.

What I'm thinking of is to remove the hardware router, set up a software 
router on a small Linux machine that I'm already using as a personal 
server, and use that to act as the router for the local network. Which 
brings us to my first and second questions: Would Zebra be a good 
solution for this, or would I still have the same issues, and what 
should I do for a firewall solution to keep my local network safe and 
secure without having to throw up firewalls on all the machines?

The issue with this idea is that I don't have any multi-port Ethernet 
cards, and I only have one spare, single-port card, which brought me to 
the idea of leaving the new software router behind the hardware router, 
setting up the hardware router's "DMZ" to send everything to the 
software router, then having the machines on the local network use the 
hardware router to connect to the software router to do the actual 
routing, essentially using the hardware router as the missing Ethernet 
ports.  Thus bringing us to my third question: If this is even possible, 
what kind of effects should I expect on performance (speed, reliability, 
overall ping, etc), and security due to the extra steps the data would 
have to take to get to the internet using this method?

I have also considered putting the hardware router behind the software 
router, but that still leaves my gaming machine behind the hardware 
router with all the others in the network, ultimately leaving me with 
the same issue.

Any and all answers and comments are welcome.

Sincerely,
Elijah Anderson