itunes as default player

I have quite a precarius situation. I have a dvd with alot of music on it. I have been having to transfer folders off the dvd to a made folder. Then I have to open the folder and play them for itunes to pick them up. For some reason I can't import them??? Anyhow, when I copy the music files to the new folder some times they are in itune format then sometimes they are in crappy music match (which I hate) After I have downloaded some of the music on the itunes, I will check the folder again and it shows them in music match form. The 2 players seem to be fighting back and forth??? Like I said I am having a hell of a time importing any thing from my hard drive I just don't get it?