The Capitol Years has all the best tracks from Sinatra’s major albums from 1953 - 61. I have had it since it was released in 1990 and played it many times.
However, my favorite album to listen to now is Sinatra & Sextet: Live in Paris. It is a terrific performance with a really lively band, that makes a change from the lush orchestrations of the Capitol sets. The sextet did one tour to raise money for charity and included Bill Miller, Al Viola and Irv Cottler who were Sinatra sidemen for decades. The album is reportedly the entire unedited performance in Paris.