I typed firewire network into WinXP help. One of the knowledge base articles (q310433) says, in part,
"IEEE 1394 on Windows XP.
Windows XP has built-in IEEE 1394 support. To use all the capabilities of the IEEE 1394 standard, your computer must have an IEEE 1394 adapter installed. If your computer has a FireWire adapter, the adaptor is IEEE 1394 compatible. Some of the capabilities of a Windows XP-based computer with the IEEE 1394 standard are:
Instant network connectivity by plugging two or more computers together (no additional hardware or software required)."
So, if both your machines were XP, it sounds to me like it would be pretty simple. Hopefully win2k can do it too.