Re: 33 combined slams vs 1 - does Murray have the right to be in a "big four"?
But right now he's unquestionably the third best player in the world (with Nadal out) - closer to the second than to the fourth - , so if this 'Big 4' refers to the four best players at the moment, then yes.
MTF games Grand Slam titles:
Suicide Tennis - Wimbledon 2014
Fill-In-The-Draw - US Open 2014