I once listened to and owned the entire series of The Giants of Philosophy, and I deliberately paid close attention to how Charleton Heston spoke about the concept of the Will in Schopenhauer's philosophy because, at the time, this was early 1990s, I was questioning how Objectivism portrayed Schopenhauer in Leonard Peikoff's course, The History of Philosophy. I was pretty sure that Leonard Peikoff was caricaturing Schopenhauer's philosophy, not truly describing it.
And Charleton Heston's presentation, while more in depth than an Objectivist presentation of the same philosophy, and while not intending to, is also a caricature of Schopenhauer's philosophy if only because the concept of the Will requires a tremendous amount of concept-building, including Schopenhauer's principles of sufficient reason, and a two-tape cassette lecture cannot replace the in-depth reading necessary to understand it, although, as the previous Amazon reviewer stated, there is no other audio lecture on Schopenhauer, so that fact alone makes this lecture worth listening to.
On the face of it, however, anyone listening to this lecture on Schopenhahuer's philosophy would be hard-pressed to be persuaded by it even if it is an honest if flawed attempt to give the listener an overview. The oddness of the philosophy presented here made me intrigued enough to read Schopenhauer's works in order to learn whether Schopenhauer had birds nesting inside his skull or whether he was concerned with something so transcendental summary-words could not adequately explain it.
The latter turned out to be the case.