If only copy from DV to VCR, you don't need to buy IEEE1394 card, just use a video cable.If you don't want to edit your video(by nonlinear edit), you don't need IEEE1394 card. If you need IEEE1394 card, you must also have a larger hard disk such as 80G above because one hour DV images need at least 15G-20G capacity.
Sorry for late reply. I am just wondering why you need to copy the miniDV tape to VHS, you can play back your video directly using your camecorder. You should find the connectors for analog video and audio output, right? or even better use S-Video output. Just ignore all digital output like USB or IEEE 1394, use the camecorder as usual analog one. That's it!