Amateur, everybody here keeps saying cross-over cable, so make sure your cable is crossed-over, this is not your standard cable, on a cross over scenario the send wire on one side is the receive on the other and vice versa, so make sure you buy a cross-over network cable (RJ45), if you have a hub it does the swaping for you.
Continuing, assuming you have a cross-over cable, plug it to both computers, make sure both have TCP/IP and use local IPs (192.168.1.1 / 2) like the boss said, this makes it simpler, then just for the sake of transfering files, disable firewalls and any other piece of software that might block communication.
Open Windows Explorer, and right click on your C drive, from the pop up menu, select Sharing and Security... and share the C drive, give the share a name, and press OK. Now make sure both computers are part of the same workgroup, doesn't matter if you have the same user account, as you will be asked for credentials.
Now, still in Windows Explorer, down the bottom on the folders list (left side), go into (expand) My Network Places > Entire Network > Microsoft Windows Network > Workgroup > Your computers are listed here (this may be slow sometimes Windows takes time to broadcast it's shares), you should see your computer names listed there, expand a computer, and you should see your shared drives, expand it and you will either see the files, or asked for user/pass to access it, that's it, now you can access the other computer easily.
Hope this could help.