Farber
I loved,
loved Umbridge as a villain. She's a big part of the reason Order of the Phoenix is my favorite book of the series. And she couldn't have been more perfectly cast in the films.
I always hated Snape. I was supposed to. But I guess I never really saw him as a villain.
OotP is my favorite one too ^^ and i agree that she was cast perfectly. she was basically perfect for the role. her voice especially is perfect, she has the sickly sweet type of voice as in the book. i imagined her voice pretty darn similar to how i actually heard it in my head while reading.
i think i'm one of the few people who believed Snape was good... it totally killed me when he killed Dumbledore, i was like "nooooooo he TRUSTED you DDDDD;" and when i found out all about him and Lily i was like "wtf you ARE a good guy o_O" and then i cried because he was dead.