hmmm ... best thing to doo is get a mpg2avi converter, there are a lot of free ones out there:
http://www.google.com/search?q=mpg2avi
... any will do, once you have an avi you could use virtualdub to split the avi into little files. just play around a little bit, but if you have no idea what codec/audiocompression/ means expect at least some days of testing until you get a decent result. but yes, virtualdub is the one you need ... enjoy !!