I would highlight the big news items of that period starting with puffing smoke, the early bulb smokers and later pellet style, Magnatraction how it was beta tested on the 622 NW2 switcher before being unveiled in 1950,  The wonderfull F3 that became the icon for that era and most wanted train (Santa Fe version).   If you have a Magnatraction engine with good strong magnets, take it and pick it up with the track stuck to the wheels as a demostration.  Talk about how plastic replaced tinplate steel in the postwar period.   Mention the iconic ZW transformer.    If GG1's or steam is your thing, talk about the highlights of those models, talk about how Lionel was once the "right arm" of Christmas.  Right up there with Santa Clause and the family tree.  You can mention the incredible store window displays of the past holiday seasons, like is seen in the begining of the movie "A Christmas story".        Mike