We're talking about who YOU first imagined the characters to be portrayed by, so don't be afraid to say which ones YOU imagined.
Stephenie's first choices were:
Bella - Emily Browning
I read the books after I saw the first movie, so it was actually really hard to imagine the characters to be portrayed by someone else. I had very similar choices to Stephenie's though when I eventually imagined other actors to portray the roles.
Bella - Emily Browning!!! She's exactly who I imagined for the role!!!
Alice - Rachel Bilson
Jasper - Toby Hemingway
The only actor who is close to the description for Jasper for me.
Rosalie - Blake Lively
Blake is absolutely gorgeous and fits the role soooo perfectly.
Emmett - Kellan Lutz
No one can be Emmett besides Kellan!
Carlisle - Nick Carter
I know this is probably a ridiculous choice for the role since he has little acting experience and is...a Backstreet Boy, but as soon as I read 'young, blond and handsomer than any movie star I've ever seen' Nick Carter came straight to my head. But as the story progressed, I headed towards someone like Charlie Hunnam.
The heart shaped face, caramel locks, 5'5 and absolutely gorgeous, who else can be Esme other than Rachel?
Jacob - Taylor Lautner <3