I have to say The Legend of Zelda series, Halo and Titanfall. Now, the reason for hating these games was because I was exposed to people who repeatedly and tirelessly said these games were better than anything else, and that "in your face" attitude from the fans that made me naturally dislike those games.
I also disliked the Mass Effect series, but that was until I tried Mass Effect 2 and fell in love with it, with Mass Effect 3 sealing the deal with the multiplayer and the... story.