Linux Novice

[steve]

I've just gotten a DSL line stuck in my house.  I have 3 PC's, 1 (New dual
533 G4)Mac and 1 New G4 Mac Powerbook laptop.  I haven't done anything yet.
One of the clones has Red Hat 5.2/WIN 98(P I 166), 2nd one has WIN98(P II
350), the third clone is a AMD Duron 800 and has no OS on it.  I want to
use it as a firewall and webserver, so I went to Fry's Electronics and I
found there are 3 Redhat boxes. A standard for $39.00, and workstation for
$79.00 and a Professional server for $169.00.
I also found that Netgear has a 1000 mbps ethernet card there for 149.00
but they did not have any 1000 mbps switches available.
Questions:

1.) Is the Professional server worth buying?
    a.)Do I need it for what I want to do.
    b.)can I buy the cheap one and download all
       the other stuff packaged with the Pro Server
       or enough RPM's to get what I need.

2.) Without getting too bogged down with the Hardware
   compat list at Redhats site, has anyone had any great
   successes with 1000mbps ether cards and swithes or
   horr stories they want to share. 

I want the Mac to run as a game server for the new game Never Winter Nights
when it ships with up to 64 people on it at one time.  It already has a gig
ether card in it. I want it to sit behind a Linux Redhat firewall as well
has I'm tire of paying to host my website, so the 3rd clone would be
perfect for a firewall/webserver. I'm too in-experienced to know exactly
which Redhat package I should get, or where to start, so some direction
would be nice if you have the time.

Many thanks.
Steve