Athens invited democracy and, although only a limited number of the population could actually participate in the government - free Athenian-Born - they actually ran the government themselves rather than just voting people into office, so as far as it went it was very democratic.
Athenians invented the first theaters and performed the first plays, They produced some notable writers and philosophers, and made some major advances in mathematics.
They created some wonderful architecture, like the Parthenon, which is still standing.
The Spartans ere more keen on making war than on producing literature, architecture, etc. However, the ancient Greeks in general created the concept of organised sporting contests (they only time they ever stopped fighting each other was for sporting events). Most Famously, they created the Olympic Games. Many major athletes were Spartans, as they were super-fit and athletic.