Convert from WMV to MP4 or re-import?
I want the highest possible fidelity with the original so I think re-importing them is the way to go but I wanted to get advice on whether that's really true.
Absolutely. Do not ever re-convert something that has already been (lossy) compressed. In the case of video, this might have a dramatic impact on the quality. It's not as evident for, let's say WMA to MP3 conversion, but still can be noticeable.
You can definitely try it, but it would take a very high quality setting (sacrificing storage space) for your destination codec in order to reproduce the quality of the original WMV video. You will see very blocky video, color errors, maybe even blurring and other artifacts.
From your DV camera to a video file
When you're re-importing, you will have to make a choice between lossless and lossy storage. Modern video standards such as h.264 are good enough so that you don't particularly need lossless encoding anymore, unless you want perfect fidelity. Still, you can't go straight from your camera to a lossy codec, at least not with software I know of.
If you're on a Mac, you can capture your videos straight from the camera using iMovie. Unfortunately, it doesn't offer a lot of settings for importing. In the case of your MiniDV tapes, it will probably use DV, which will take a lot of storage space, because it is the "native" format that comes from your camera. The thing though is: These DV files being imported are lossless — that's why they're so huge.
What to do after importing
You can now choose to keep these DV files and work with them (iMovie will do that, as well as other video editing software), or convert them to h.264-encoded video. Probably the best encoder for h.264 out there is x264, and it comes with tools like Handbrake. It will create MP4 files for you, and these should be compatible with all modern platforms and applications.
If you decide to convert your DV files into h.264-encoded video, make sure to choose the High Profile in the presets bar when using Handbrake. This will try to retain the quality of the original DV video, using everything h.264 has to offer.

Personally I would re import them to the format you desire. – Moab – 2011-12-09T18:02:55.890