For a long time, 'The Menagerie' was my favorite 'Star Trek' episode though in recent years it has been eclipsed by 'City on the Edge of Forever.' What I used to prefer about 'Menagerie' was that it's more hard-core Star Trek with this fascinating back-story to the then-current Trek storyline. I still think it's fairly ingenious the way Gene Roddenberry incorporated the original pilot into a two-part episode. Though the 'new' part of the story is largely an excuse for Kirk and a few others (and us) to watch the pilot, the idea of Spock being court-martialed is a clever one. You can poke holes in the plot if you want. For instance, given the Talosians' mind-control abilities and Captain Pike's condition, why is it even necessary to physically bring Pike back to their planet? And there are other confusing questions about Pike and Commodore Mendez... best to not think too hard about the details and just enjoy ST's only two-parter.
Review of The Menagerie: Part I
