I think Nightrider has answered the question you asked me earlier.
Have a look here for widgets
datavision there are 2 types one like you describe and another that will plug straight into the fire wire/dv-in/out port on you camera.
There is a compatability list which shows the DA1B as compatible to both types. Might be worth mailing or ringing them first to make sure.
DV capured film is of a very high quality abd can be encoded to DVD, which is more or less with no loss of quality.
Once you start re encoding you will loose some quality.
In my opinion DV quality is the best. You can output it wherever you want, tape, CD or DVD, or back to the camera.
Is the pinnacle card a analogue or digital capture device. If it is digital then as long as you can output it to tape then there would be no need to enable the camera for DV in.
Re reading your post it sounds like all you need is a firewire cable to connect your camera straight to an IEEE1394/Firewire port on your pc, which should be a lot cheaper than getting a widget. You won't need to dv in enable the camera if you can output to tape tghrough the pinnacle card.
Hope that helps