can I use musics

contains midi files , have I the right to use them in my blender games and publish them

Ask them, not us. And you’ll have to convert MIDIs to WAV before they’ll work in blender.

Yeah, VGMusic has a nice selection of music. The thing is you have to ask the individual author if you can use his/her file. Remember, the site owners didn’t make the music, the people did… well… they synthesized it. Either way, look around in the FAQ or something and it tells you to get individual permission for every selection of music you want to use in a game or something…