Hmm, I think you'd have a better time formatting it for FAT32 because OS X can read this AFAIK. And you wouldn't be able to store programs on it, or you shouldn't, because you couldn't run them on the other machine, and I doubt MOX apps would run on a PC drive anyway.
That drive looks like a good deal. You could get it and try plugging the FW port into your Mac and the USB port into the PC, though I don't know how this would work, if it would at all. Also, if you have an ample internal drive in your Mac, you can plug a Firewire cable from your Mac to your PC and boot the Mac while holding down "T," booting into Target Disk Mode.