For the 1960's? Surf Side. Best 2-player of that decade, period. But ONLY fun with two people! A-Go-Go and Expo also very good when dialed in. Cosmos for honorable mention.
1970's? Out of Sight/Far Out, Sinbad (SS version), Joker Poker (SS version), Skyrocket, Wizard!, Old Chicago, Freedom (prototype), Aztec, Space Odyssey/Mission