Haifag, people who refrain from listening to “non-Jewish music” are not avoiding a precise tempo, key, or sequences of notes. They don’t listen to music with secular lyrics that has been composed by, and disseminated to, the non-Jewish population. Generally, if the intent is to provoke behaviors that are not in keeping with our standards (which can usually be discerned), the music is frowned upon.
I know this answer won’t satisfy completely. Mozart and Beethoven were not Jewish and their music is considered by just about everyone to be acceptable. And too many Jewish singers and composers to list plagiarized or parodized (-not a word? I’m sure you know what I’m saying-) non-Jewish songs. But it’s the best I can do for now.
If you are sincerely interested in staying away from music that’s not good for your Neshama, then a good barometer is your own Neshama’s reaction to the music you’re listening to.