Gorbachev secured his place in history by what he didn't do. While never endorsing the end of the eastern bloc, he made it clear beginning in the late 1980's that unlike his predecessors, he would not oppose democratic reforms in Eastern Europe by force. To general astonishment, he kept this promise, and with the regrettable exception of Lithuania this commitment to not repeating the crimes of his predecessors is Gorbachev's greatest legacy. In 1988 you would have been hard pressed to find anyone who could imagine the mostly peaceful collapse of the Eastern Bloc, but Gorbachev had the moral courage to accept this once unimaginable consequence of his policy and to see it through.
Not to pick a fight, but I feel it's important then to note that it was not Reagan who "won" the Cold War. It was Gorbachev, who had the political courage (and idealism) to take the leap.
The people who "won" the cold war are those Eastern countries that had been occupied by Russia for 45 years and fought for their freedom in Prague, Budapest and especially in Gdańsk.
Russia has also won the cold war, as it was, too, liberated from cumminst tyranny and quaity of life and freedom have raised significantly as a consequence. Sadly, this consequence took time to take place, which made the causal relationship not obvious for many Russians, and a lot of what Russia has won over this liberation has been gradually lost since Putin came into power.