But this really points out flaw in how the general public, including journalists, understand academia. If I were to describe Eric Lander's professional appointment (or nearly any other research professors appointment, for that matter), "teaching" would not be the first item on the list. In fact, a lot of profs don't teach at all. Research comes first, then advising grad students and post-docs (which is a kind of teaching, but not the in classroom variety that I imagine most people picture when they say so-and-so teaches at a university) and getting grants (which could be bundled, along with writing papers, under the umbrella of "research"), followed by teaching (if they do that at all).
This doesn't mean that teaching isn't important, but it's not what research scientists spend most of their time doing. These people, the ones at research schools that is, became professors in order to be active research scientists, and not primarily teachers. (That's not to say there is anything wrong with highly competent PhDs who work at schools where the teaching load is heavier - you choose a job based on your interests; teaching science is an excellent profession.)
In other words, no, you don't get a vacation when classes are not in session, and yes, you have a hell of a lot more to do than just teach 2 classes a semester, contrary to common opinion.
And just to harp on one more common misconception about science careers: no, postdoctoral fellows are not students (I already have my !##@!& PhD), so don't ask me when I'm finishing school!