Rules of thumb to follow.
#1 NEVER use overplayed recent radio songs.
#2 NEVER use songs that have been overplayed in the bodybuilding
world. Ex.Conan Music
#3 Don't use gothic (conan) dramatic type music UNLESS you're a TRUE freak and are going to shock the world. Nothing looks worse than an average physiqe trying to pose to dramatic music like the pro's sometimes use.
#4 Try to stay away from Heavy Metal, nobody wants to see that shit anymore.
And finally
#5, just be ORIGINAL.