ICS under Windows 2000 Server

I have been trying to run ICS under windows 2000 server but I cannot get any clients to connect.
I have disabled DHCP WINS and DNS on the server.
I have also enabled internet connection sharing and on-demand dialing for my modem dial up.
The servers NIC ip is set to 192.168.0.1
All the client pc’s NIC’s are set to “Obtain an IP address automatically”
The local network is running fine because all the shared volumes are available and I am able to ping all the clients.
All the clients browser settings and mail are set to connect via a LAN.
Am I not seeing something so obvious (Wood and Trees springs to mind)
Thanks for any help in advance, this is really bugging me.