"He's convinced me, gimme back my dollar!"
Mr. Orange says this after Mr. Pink goes on a rant about why he doesn't tip while all of the guys are at a diner sorting out paying. Most are against Pink but Orange sees the sense in it and wants his tip money back.
"Are you gonna bark all day little doggie, or are you gonna bite?"
Mr. Blonde has been missing but finally shows up sipping a soda while Mr. White talks about him. No one knows who the rat is and since Blonde hasn't been there he is one of the potential traitors. This statement is also the beginning of Blonde's violent streak that we experience in the film after his massacre at the bank.
"Joe, you kill that man you die next. I repeat: you kill that man, you die next."
Mr. White has come to a crossroads. Joe is ready to execute Mr. Orange for being the traitor but Orange has become like a son to White. So he believes him to be innocent and is willing to kill the hand that feeds him in order to protect him. In the end, Joe was right and White kills Orange himself.