some of my other faves:
Yuna: You will go with us, to Zanarkand?
Tidus: No, no, no, no!

Wakka: Don't get any ideas!
Tidus: I HAVE to!!!

Tidus: I HATE YOU!!!
Rikku: Oh!! H-Honest?
Tidus: I-uh...
Rikku: Sounds good to me!

(btw that part with Rikku is what happens at Guadosalam if you flirt with her instead of Lulu)