Hi Matt, not sure if this works on PC's (I work on Mac - which is much easier! lols)
Shut down the Computer that you want to transfer info from.
Plug the firewire into Both then restart it at the same time holding down the 'T' on the keyboard. When it's booting up you can let go of the T - it won't boot up properly. On a Mac you get a blank screen with a symbol bouncing around.
The newly started computer shows up as an external drive(?) on the other PC, which you can then access. (Or at least it does on a Mac ... apologies if this doesn't work on a PC)
I'm sure that some very technically able PC Guru will be able to correct me, and offer advice if this doesn't work on PC's. Good luck!
Mort