Converting .mkv movie for DVD

I am trying to convert a .mkv movie on my mac G5 - it is in MKV format (matroska video file). I have only been able to view this movie by using the VLC player which a friend recommended to me as a good all around player which recognizes most formats. Now I am hoping to convert this mkv movie for dvd - i am using dvd studio pro but when i tried bringing it into compressor it did not recognize the file format in order to convert it into MMPEG2 & aac.

I am hoping to find a good conversion tool for my mac to keep the quality high and create either quicktime mov's or mpeg & aac - any suggestions people?

Ideally i would keep the quality at the highest possible for this almost 2 hour movie and then I think worry about compressing it for dvd using Compressor before bringing it into DVDSP.

And you might want to check this out on Version Tracker. I find the Feedback/Comments reports entertaining and informative.

http://www.versiontracker.com/dyn/moreinfo/macosx/23606

So i downloaded this thing called "MKVTOOLNIX 2" and i am totally lost now on this interface and how to make either .mov'x and / or mpeg2 & aac - ultimately i just want to burn this 2 hour mkv format movie using dvd sp or toast but it seems very complicated...any other advice?
thank you

I also just tried this app - MoKgVm2DVD which makes .avi & ac3 but which dont seem to play / open in quicktime - i though i had it but alas no luck - unfortunately its for a personal project so i cant bill thw research and work - thanks again for your time and help - you rock
best
Bk