I like mum's new blog. The diary of a procrastinator! Did mum make the scones, or didn't she?!!

I have a question.... when I first downloaded iTUNES onto my laptop, it asked me if I wanted iTUNES to be my default music player and I accepted. But now I don't want it to be- because it means when I'm playing the music dad downloaded for me, it keeps diverting to iTUNES. How do I change it? Any suggestions?