i irrationally hate the actor that played the mother from How I Met Your Mother. Maybe i just hate that doe eyes look she seems to be inflicted with. And she seems to always be playing some sad sack in a bad relationship so it might just be type casting too. Plus the end of HIMYM was so fuckin bad so that might not help lol.
Mel Gibson. I hate him because he's a Christofascist antisemitic piece of shit but he also, in my opinion is a good director (and a mediocre actor). If his some of his movies (Apocalypto, Passion of the Christ) weren't so thoroughly reactionary in their underlying politics, I would happily recommend them to people.