Home Networking Help Needed!

Hello there. I recently got a 2nd home computer so i decided to network them to share files and the internet. Both are on Windows 2000 professional and i got 2 network cards - a netgear and a 3comms which i have installed ok and are working. I have cat 5e cable and when plugged in both cards show a connection made. One seems to sends bytes and the other packets so i dont know if this is a problem. I am sure i dont need a hub as there is just one connection. To no avail i have tried to set up the Internet connection sharing but i think it is wrong as my main computer with the broadband sees 2 computers in the workgroup but the other computer cant access it. Can anyone help please as the broadband uses an ATM conection as it is a USB modem and i dont know if this is a problem? Could someone please give me a guide step by step to set the home network up to share files and internet as i am also confused about hosts and clients and using \\ in the My Network Places. I am at my wits end!

They are both in PCI slots. On ipconfig it shows they use Autoconfiguration IP Address and Subnet Mask but they dont have a default gateway. Yes they can ping each other. My computer with the broadband can access the network and get files from the other computer without internet but i cant do it the other way round. I want to access internet and files on the computer without internet but it wont let me when i enter the workgroup. It seems like its just working one way as the broadband computer node is broadcast and the other computer node mixed.

I used crossover cable. Both are sharing folders but only one computer works. The other says it is not configured for transactions when entering the workgroup.