I am a sheep...
Or a lemming, if you prefer the reference to an Old Skool game...
I've always been partial to the Opera Scene myself, and because of that part of the game us geeky Old Skoolers have access to the 23 minute Dream Oath Opera audio file. That and you first meet Setzer, the pimpingest pimp ever created.
Apart from that obvious choice, I would have to choose the part where you first feed Gau the Meat in the Veldt. Mr. Thou! Cracks me up every time...