I know you may not want to hear this, but after trying multiple ways to import MiniDV videos, I found that Quicktime (I’m using version 10.5) is actually the best. It respects the aspect ratio, allows you to bring in uncompressed video, and you can start and stop the tape if you want to, for separate files, or you can just import the whole thing and cut it up later.
You can also use Final Cut Pro X, which will do a nice job.
But I wouldn’t use iMovie.
Hook up your camera to the computer. Open QuickTime. Choose File – New Movie Recording. When the recording window opens, click the little drop down arrow next to the record button and make sure your camera are microphone are selected to your camera, and the quality set to maximum. You can play around with Maximum vs High quality. I went with maximum since hard drives are cheap these days. 🙂
Good luck!
Daniel