I personally use Audiojack v1.5(pay program) to do my song editing, but I'm no hardcore media guru. I like it because I can silence or reverse (and thus make unintelligible) the most common file formats, and it's pretty idiot proof. However, if you have the know how, pretty much any sound editing program will work. For instance, if you use Windows and the song you have is in .wav format, I think sound recorder would do the trick. On the other hand, you may need to change the format of the file, download codecs, or even do some system tweaking depending on the file/your editor(mixer)/the quality you want. I'm fine with 128kbit/s, since I listen to my music on an mp3 player, and really don't care too much about lossless and CD quality. I also use Audiojack to maximise the unrestricted mobility and utilization of my music. There are probably better (and cheaper) programs out there, but Audiojack continues to come through for me so long as I keep my versions of lame and ogg up to date. As for setting "the songs to hade adult content" I don't understand what you want to do. Maybe you could explain in a little more detail what you're trying to do?