I came to a number of widespread-but-already-fading 20th-century cultural touchstones indirectly — as I think did many of my generation — mostly through Peanuts and The Simpsons. The first time I heard the Roy Cohn gag in the “Homer’s Barbershop Quartet” episode (season 5, aired 1993), I didn’t know who Roy Cohn was, but I understood the cadence of the joke and the implication of the old-fashioned radio.
i, too, was a child of the late 20th century with a lot of dated cultural touchstones looming large in my head - partly through Peanuts and the Simpsons but also because i loved old paperback MAD Magazine collections i found at used bookstores, cassette tapes of old-timey radio shows, and, yes, crossword puzzles, which until pretty recently were often premised on the idea that the person doing the solving was born in 1937. i think the 80s were a really peak time for that sort of backwards-looking culture - what with the President being a washed-up 1940s movie star, among other things.
(somewhat related: i am often struck by the relative gaps in time revealed in considering pop culture. see, for instance, the way the Indiana Jones and Star Wars movies are considered a major touchstone in themselves, but for their creators were loving homages to the serialized B-cinema of their youth. a time-equivalent version of "The Wedding Singer" released now would take place in 2008.)
It's a recurring conversation between my Dad and I anytime I reference something way too old. "Where you'd hear that?" "Probably The Simpsons, or Animaniacs, or that one episode of Wishbone..."
Encarta MindMaze! I was all about that game. And yes, I love old movies (and shows) for that reason too, or coming across references to things that I didn't know were references. Like I somehow came across the fact the Hardcastle and McCormick was an old detective show and not just Brad Neely's name for McGonagall (Professor Hardcastle McCormick) in Wizard People Dear Reader. I eagerly await the Horsefeathers one! (Now I'm thinking about the DISRESPECT of film critics who for years thought Margaret Dumont wasn't in on the joke.)