Don't change anything. OSX can read and write to FAT-32 volumes and can read WINNT drives.
We did have one PC drive that the client delivered that we couldn't read. Nobody ever figured out why, but we got one of the producer's PC laptops to read the show for us and blow it back onto one of our drives.
I would have a portable hard drive big enough to contain it all available. Empty. You may need to change the format to FAT32 in an emergency and that destroys everything on the drive.
You may be stuck with USB, too. Relatively few PCs have FireWire--so get dual USB/SFireWire.
Koz