Yes you can stop but do not finalize the disk. You can add later or continue after stopping the burning. On CD-RWs it is a lot easier for there you can delete, add and format. CD-Rs have to be finalized after burning for them to play music/MP3s on players, if not, then they won't play but you can add to them. If you burn ONE song to a CD-R and finalize it, you will NOT be able to add to it eventhough you have "oodles" of empty space on it.