You've got analog tapes, so one way or another you're going to have to "capture" the video. You can use a graphics card, one of those dazzles, or a camcorder, or a number of other ways. I'd use the MiniDV if I were you. Also, most MiniDV cams can do something called "passthrough" which will just let the video simply passthrough the miniDV cam right to the computer via Firewire (or USB2). That feature can be useful depending on what you are going to do. For starters, it'll let you skip dubbing to a miniDV tape altogether, which could save you a bunch of tapes and more importantly spares your tape transport/heads from the mileage. Secondly, if you do want to archive to tape as a sort of master for future use, the passthrough can still be helpful because typically you can capture to MiniDV tape AND passthrough to the computer simultaneously -- which gets you the masters on tape, but gets you the digi files on the computer in one step instead of two (again, this saves wear and tear on the heads/transport because you'd have had to record it first, then capture it next, so it will save you one pass in real time). Lastly, depending on what you're doing exactly, you can actually feed the passthrough signal right into an encoder on-the-fly that can pump out MPEG2 in real-time. Now, that's not the best way to encode to MPEG2 (two-pass variable bit rate would be better), but man that saves a whole bunch of time if that method works -- you can tape a master to MiniDV while passing through DV to the computer which in turn encodes to MPEG2 on-the-fly so you end up with a master and a DVD-burnable file in one pass in real time. That approach also only puts an MPEG2 file on your computer, which will obviously be MUCH smaller than loading a full DV file, which can start adding up real fast in HD space if you are converting hours and hours of footage (10-13 gigs/hour for DV as opposed to maybe 20% of that for the MPEG2 files). However, if you are going to edit the video, then you'd probably want to work with the DV files in your NLE and render/encode out to MPEG2 later.
Anyway, just some thoughts...