Well I got quite a shock after reading all the information copyright. I knew that you were restricted with what you could use in presentation's/slide shows but I didn't realise it went beyond that. I think the Royalty Free music available on incompetech is really handy as you don't have to worry that your doing the wrong thing.
I think music in the classroom is great and not used enough. It can be used for educational purposes and for creating a classroom environment that is relaxing. Music I think is a great way to explore different countries and cultures. It also adds a fun element about the unit or lesson as the students can have a dance.
I downloaded a few songs that were of African origin. I think this music would be great for students to listen to in class during a unit of work on different countries. There was also other music from different origins that you could use depending on the country you were exploring. I also don't think it would hurt to have music from different countries playing in the background when appropriate so students were exposed to different cultures.