I'm bored, and going to post all the ones I remember:
Lois: Peter, what did I ask you not to do?
Peter: Drink at the Stag Party.
Lois: And what did you do?
Peter: Drink at the Sta.... oooh ho ho, I almost walked right into that one.
Quagmeyer: Man this itches. I wonder who gave it to me. I bet it was that skank that needed a ride to the gas station. Last time I do a favor for anyone. Hey, I can hear me! Oh my god! They can hear me! BANANANNNANANDDNANNANNAAA!
Death: Which one of you is Peter Griffin?
Peter: *holds up lamp* This... is Peter Griffin.
Death: Haha, my god, thats good.
Lois: Why ar...
Death: Hahahaha....
Lois: Why ar...
Death: Wait, wait, I'm not done, holding my sides, hahaha...
Lois: Why ar...
Death: Hahahahaha! *the two stare at each other, before Lois starts again and is allowed to talk*
Peter: Mr. and Mrs. Ramsey, I will not stop till I find your daughter's killer.
Mrs. Ramsey: It's okay, we'll manage.
Peter: No! I swear, I will find the person who did this!
Mr. Ramsey: Really! We're fine!
Lois: Are you mad because you went wee-wee on the carpet?
Stewie: What was that?
Peter: Hey Lois do you...
Stewie: Not now. Mother, bend down. *Lois bends over and Stewie slaps her with a glove* How dare you sully my good name you vile woman!
(a little later, or before, I forget)
Lois: Peter, Stewie peed on the carpet.
Peter: Do I... Do I hit him?
Greg/Peter Gumble: Did you steal the purse, or was it society that made you steal it?
Criminal: What the hell are you talking about, I wanted her freakin' purse!
Gumble: Umhm, mhm, mhm, mhm, mhm, mmhmm, mhmm, mmmhm, mhmm, mhm, mhhmm (it goes on till its funny)
Meh. Lack of motivation setting in...