I will bite, and good god there are a gazillion choices ... I know I am "guilty" of gravitating to the big license games:
El Dorado (love the drop targets)
Space Shuttle (easy to understand, my favorite for a quick game)
Indiana Jones TPA (just a great all around pin in all ways)
Lord of the Rings (modern classic)
Wizard of Oz (best looking pin ever, toys and mechs galore, a real engineering feat)
Jurassic Park (dinosaurs AND a great game, yes please)
Honorable mention is Wonka, love it.