Inigo Montoya

Hello. My Name Is Inigo Montoya. You Killed My Father. Prepare To Die

The scene where Inigo has Count Rugen cornered, begging for his life, builds up to a truly awesome line.

Inigo: HELLO! MY NAME IS INIGO MONTOYA! YOU KILLED MY FATHER! PREPARE TO DIE!

[Inigo corners Count Rugen and slashes his cheek, just like the slash he gave to Inigo as a child, then starts taunting him']

Inigo: Offer me money.

Rugen: Yes!

Inigo: Power, too, promise me that.

[another slash]

Rugen: All that I have and more. Please...

Inigo: Offer me anything I ask for.

Rugen: Anything you want...

[Rugen knocks Inigo's sword aside and lunges. But Inigo traps his arm and aims his sword at Rugen's stomach]

Inigo: "I want my father back, you son of a bitch!"

Westley

The entire To The Pain speech.

Buttercup

"You can't hurt me. Westley and I are joined by the bonds of love. And you cannot track that, not with a thousand bloodhounds. And you cannot break it, not with a thousand swords. And when I say you are a coward, that is only because you are the slimiest weakling ever to crawl the earth."

The Grandfather

The sardonic, punctuating wit with which he keeps his grandson in place needs to turn up just a few times to be hihgly memorable. One of the best bits:

Yes. You're very smart. Shut up.

Fezzik

"The Dread Pirate Roberts has come for your SOUUUUUULLLLLL!"

Fezzik

Fezzik has his own at the end: he comes with four white horses he procured in case he ran into Inigo and Westley after they saved the lady ("Hello, Lady!") and explains it in a much more articulate way than his simple nature would allude to. As Inigo points out, Fezzik, you did something right. ("Don't worry, I won't let it go to my head.")

Westley

I Am Not Left Handed either

Inigo Montoya

I Am Not Left Handed

Westley

"They were both poisoned."

Buttercup

I-I-I... AM... THE... QUEEEEEEEEEEN.