As for you asking if classical music can be "kicked to the curb" because it doesn't have a vocal line, I say don't be ridiculous. Melody doesn't have to be vocalized...I used that as an example because in today's pop/rock/country/R and B/soul genres, the vocal line usually is the melody. Obviously, in classical, jazz, and other instrumental genres, the melody is performed on the trumpet, the violin, the piccolo, whatever instrument happens to have it at any given time.
My point is that in rap/hip-hop/whatever you want to call that garbage that I hear being vomited out on 98.7 and 95.7 FM in the Tampa Bay area, there is no melody. From time to time, you may have a chorus that is sung, and if you want to split hairs, I guess I'd have to concede that for that brief passage there is a melody line. But then it goes back to the primitive fart noises that rap is. Just try to whistle along with it...you can't, because there is no melody to whistle. A little riff on the keyboard, a bass line or a few chords on a guitar in the background doesn't qualify as melody, either.
Now whistle along with "Carmen Suite", or any of Beethoven's symphonies. Whistle along with "Freebird", "Green Grass and High Tides Forever", or anything by the Allman Brothers. Whistle along with anything by Kenny G (if you can do so and hang on to your lunch, that is). Yes, that's right...you've found melody. The instrumental accompanyment is the harmony, and the percussion and bass lines are the rhythm. Now listen to "Rapper's Delight" and try to find a melody anywhere. You can't because rap/hip-hop has no melody. It is partial music.
As for embarrassing myself, sorry bud. If you think Missy Elliot, Outkast, Mos Def, etc. are music, then you're the one who should be embarrassed. You obviously have no idea what music is, other than what's called music by your favorite room temperature IQ DJ at the local hip-hop station.
Scouts Out! Cavalry Ho!