A fourth option ought to be in there: all.
It's unfair to say which race is better when each race is balanced out like a super complex rock-paper-scissors-lizard-Spock, we are entitled to which race we prefer. Personally, I can't say which race I love the most. Terran works best for me, Zerg I'm comfortable using, and I always was and probably always will be shaky with the Protoss. How skilled a player is with a race derives from their strategy. Mine is "a good defense is a good offense." Basically, I hunker down with good defenses, upgrade to fullest capacity, build a massive army, and then strike with a two pronged attack: flyers from behind, ground forces the front (exception being the Zerg's Nydus Worms and the occasional Protoss Mass Recall). I may throw in the occasional early-game scout-raid. So, based on my strategy, the Terran are best suited for me.
And just for the record, I don't play online anymore. I took the 5 1v1 placement matches, and... well, let's just say that some people take online gaming a little too seriously. Or perhaps RTS online gaming isn't my forte, as I'm fair in Halo, Gears of War, and Call of Duty.