A single song is an individual work. If you wanted to make a "Best of 80's" CD that would be a collected work. If someone copies a single song from your best-of CD, well, that's not really your problem because you don't own that song. If someone copies your whole CD, then you've got a case if you registered that particular collection.

The list of songs on CD isn't copyrightable -- it's a fact, not a creative expression. Taking a 5 second sample is most likely to be considered fair use.

I don't think any of this is too far off from common sense.