Actor Allusion: In an episode about Manhattan, Pumbaa says that he wants to see a musical about "Guys and Dolls". This was because the voice actors of Timon and Pumbaa were in that musical..
Keep Circulating the Tapes: It depends on which country you live in. The U.S. only got six VHS tapes (with three shorts per tape), or the equivalent of three full episodes. However, Europe got more on VHS, and also got three DVDs. No matter the country, however, there are still plenty of episodes not on home video.
Really, everyone at some point except Rafiki. According to IMDB, Timon had four different voice actors over the course of the series (including Quinton Flynn), and even Pumbaa got a replacement voice actor at one point.