The previous post left out that they must be on the same subnet.
If you want to get REAL simple, install NetBEUI and Client for Microsoft Networks on both computers and forget TCP/IP. For what you want to do it will work fine. TCP/IP doesn't make alot of sense for two computers. Besides, NetBEUI is faster. It's not routable but that doesn't matter for your setup. Make sure they both have the same Workgroup assigned and enable File and Printer sharing on both machines. Without doing that, networking them is useless. Then make sure you share the C: drive on each computer with "Full Access" enabled (or whatever folder you want to share).
Brian