Some kids like music. Some kids don't. I was very proud of my 4 year old today. He usually likes techno, and that general kind of kiddie music. Today he asked to listen to Classical at bed time. He likes Vivaldi and Beethoven the best right now. I think a lot of techno is as interesting auditorily as some types of Classical. The tempo changes and the layering of different types of pitches and sounds is similiar.
My dad likes metal, and he put some on today, just in a random mix, and my boy started instantly bouncing around in time to the heavy drum beats. He obviously liked what he heard, for the short time I let him. I think he's gonna have to be a lil older before he really gets the concepts inherent in metal. I wouldn't let him listen to it for long, and I dont' think it's a good thing for him to listen to metal yet. For the same reasons I haven't introduced him to religious and spiritual beliefs yet, I don't wanna indoctrinate him at an early age with concepts he can't actually understand yet, even though he is a pretty smart kid. Raising kids is tough, because you want to teach them enough for them to make informed choices down the road, without doing what some parent do, and just brainwashing them into behaving the way the parent wants them to. It's a fine line sometimes.