On the winxp ics server side:
Right click the home netcard > properties, CHECK "Internet Protocol (TCP/IP)", then click on properties > check "Use the following IP address" and input 192.168.0.1 as ip, and
255.255.255.0 as subnet mask, other fields are left blank.

On the knoppix client side:
ifconfig eth0 192.168.0.200 netmask 255.255.255.0 up
route add default gw 192.168.0.1 eth0
echo nameserver 192.168.0.1 >> /etc/resolv.conf


That is how to make knoppix be an ICS client. Sounds like you want to make knoppix into a gateway/router though...