Lessee... Most of these are guesses :/
1) Hey, cool! It points North! Science is fun when you know the secret.
Guybrush, Curse after making the compass
2) You're pretty good, boy! But let's see you follow this...
Van Helgen to Guybrush, Curse during the banjo duel on Plunder
3) My plans for the governor are far too important.
Lechuck in Escape?
4) Mr Brush? Is that you?
Wally! In Curse, first chapter
5) Curse the villains! They never give you enough slaw with these value meals...
LeChuck, Curse during the cutscene with Dinky Dog
6) Wow, it works both ways! That's some chicken!
Guybrush in Secret, when going to see Meathook the first time
7) Hey! He stole the duck!
Someone in Escape after you steal the duck? (Gosh how clever)
10) I thought if I died, I'd be buried with your aunt.
Guybrush to the Goodsoup guy after 'dying' the first time, I think
13) Whaddya say, men? Shall we make him walk the plank?
Mr. Fossy to his crewmates after you get caught sneaking on his ship
14) That sure was a close one. Thank goodness I'm safe...now...
Guybrush in Curse, not sure where
17) I'm one gifted with a second sight.
Voodoo Lady?
21) Guybrush?
I'm guessing Elaine after they fish Guybrush out of the water during the opening of Curse
24) I'll be back!
Murray?
29) Yup. Who knew?
It's Guybrush, but I can't remember where... In Curse I think...
Easy to guess which of the games is still the freshest in my mind huh?