Rogue - Anna Paquin could have given an awesome performance had the script hadn't been changed for the original write up where she was depicted as 21 and her meet-up with Logan was in the train but with him stepping in because she was being harassed by three guys. She was still emo (ugh) but she was also tough.
Anyway - the Rogue in the movies was a travesty.
Emma - January Jones. Yes, the script had much to be desired but she played the character horribly. She came off as one of the Stepford Cuckoos, not the White Queen. One of the biggest disappointments, for sure.
I was unhappy with Jean as well -- and Storm to an extent and UGH -- Cyclops!! How could I forget poor Scott!!!