Same question across most of the 1st world and what gets a lot of votes is the 1950's-1990's. ww2 done, depression recovered, anti-biotics and decent medicine and surgery, equal rights, any man can afford an education or become president, job promotion by merit, a single income buys a house and supports the family, less than half the current incarceration rate, always some new discovery happening, we really believed we'd be living on jupiters moons by the year 2000, and it wasnt crazy thinking, we went from steampower to space flight in just a few decades after all, back then science meant BIG changes, not just different sized cellphones each year and Musk unveiling bullet proof toasters.
