MiniDV (little cassette tapes) or Mini-DVD (miniature optical disks you can stick in a set-top DVD player and playback)?
The former is the format that you would use if you intended to edit the video, and the latter is the format you'd use if you simply wanted to playback the video as it had been recorded without modification. They are not compatible formats as the physical media is different, but so is the data stored on those media.
A MiniDV camera minimally has an i.Link / mini-FireWire400 port on it for data transfer to the computer. The computer can control the camera through this port, use it either as a live camera, or operate it as a VCR and capture the video as it plays back into the computer. MiniDV video is captured real-time from the camera, meaning that if you recorded 60 minutes of video, it will take 60 minutes to transfer to the computer. The capture data will be in DV format, which is effectively uncompressed 720x480 at 29.995 frames per second (for camcorders using the US' NTSC standard video resolution anyway).
On a Mini-DVD camcorder, the camera may not have a port for connecting the camera to a computer to transfer the video. If it does, it is probably a USB or mini-USB port that allows the camera to be used by a computer as an external DVD recorder. If it is a without-connector model, transferring video would mean taking the mini-DVD out of the camera and putting it in a computer -- however Macs cannot take the mini disks and require and external DVD drive to read them. The MPEG2-encoded video on the DVD drive is highly compressed and not really suitable for editing. Manipulation of the content will necessarily degrade it, so you will lose video quality in the process of handling it, reencoding it, and reburning it.