Since your camera has no firewire, you'll need to capture your video through an analog to digital device. Either a analog to digital capture card, another camcorder with analog in and firewire out, or a breakout box for converting. In any case, the captured video can then be used by any editing application. I use Adobe Premiere Pro 1.5 but lesser expensive applications are available.
I guess I should have asked what format is the minidisc recording in? Depending on the format, I would think you could just put the disc in your computer DVD drive and read the file. Compressed files and editing can be done but often don't work very well. Find out the recorded format and search for an editing application that supports that format. You won't need a capture devive.