internet help

See here's the dealiosis
*I have two computers
-One is a dino pentium III dual booting ubuntu 8.10 and xp pro 526mb RAM
- The other is a dell demension with celeron D 256 mb of RAM (xp home only)

my dell being newer has the lan/wan card and one ethernet port. the other has an ethernet port only. Can you see where this is going?
I want to use my dell as a magical "modem" if you will to connnect my dino
to internet with a ethernet/crossover cable connecting the two and my dell to connect them both to internet through it's lan/wan card. The lan/wan is belkin wireless g card. Both the pc's have usb, cd read and write, one ethernet, and windows xp.

I have atleast four cables i can interchange

I have...

cable--> modem (cox, mind you) --> router --> computer one --> computer3 and my dell computer

I want...
cable -->modem (still cox)-->router -->computer one -->
computer3 and my dell computer <--Dino
if that makes sense.
i know that the cables are ethernet or crossover, just not sure which.

two are marked TIA/EIA-568B.2
the other is bright green and is marked gigaspeed
any help?

Now i have a 2nd router
it is one of those 2wire ones.
it does not have any dsl
i still have internet on my dell though

well since no one has replied here, the best I can offer is "try google searching"

tried that, this is the best I found, https://help.ubuntu.com/community/Internet/ConnectionSharing
and this http://www.helpwithwindows.com:80/WindowsXP/howto-23.html