WinXP TCP/IP and ICS not working

Ok here is my situation and here is what I've tried.

Right now I have cable modem coming into this computer,
then from another NIC it is running into the hub and then
into my wifes computer.

I have ICS Enabled and i get no connectivity via TCP/IP
between the 2 computers.

However I can see each computer when I have IPX/SPX
installed but when I uninstall it I loose all
connectivity.

Previously I had a windows 2000 server set up connected
to my cable modem router, then the server to the hub and
then to my computer and my wifes, it worked fine EXCEPT I
could not see my wifes computer from my machine or vise
versa over TCP/IP. The Server could see both of our
machines and each machine could see the server but as
stated a few minutes ago neither mine or my wifes
computer could see each other.

Currently the only way i can get Internet access for both
computers is to connect them both to the cable modem
directly and that means they get seperate IP address
(completely different classes) and that means I have 2
computers I set up firewalls for.

If anyone has any idea what could be going on that'd be
great.

Also, I use trend micro pc-cillan on both computers and
have completely disabled it to try to see if that was the
cause of it.

When I do a ipconfig/renew from my wifes computer in its
current configuration it just times out.

Thanks