while on the terminal, log in as root and then run these two commands
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -I POSTROUTING -o eth1 -j MASQUERADE
Now start PCC and then set up eth0 to have the following network properties:
IP address: 10.10.10.10
netmask : 255.255.255.0
PCC will complain about not being able to successfully create a connection, ignore the complaint and finish up.
Now connect a wire on this eth0 interface to your LAN and then set up a computer on your LAN to have the following network properties:
IP address: 10.10.10.20
netmask : 255.255.255.0
gateway : 10.10.10.10
This other computer on your LAN should now be able to go online,assuming eth1 is connected to the internet.
You have successfully used your computer as a router. If you can access the internet on this computer that now acts as a router,then all computers on your LAN with a gateway address that matches eth0 address will also be able to go online
You do not have to use the addresses i provided, I gave them as an example and for your convenience if you do not know the basics of network addresses.
explanation for those commands will be in the article

we will discuss the statistics part after this first part is working.