A Vimes scene which comes to mind is the bit in Feet Of Clay when he's been set up, and people come in expecting him to be drunk.
But he has so many great scenes!
My favourite Granny Weatherwax scene is her confrontation with the vampires at the end of Carpe Jugulum.
"Peter Piper picked a peck of pickled peppers," he snarled, prodding the man in the chest. "A peck of bloody pickled peppers Peter Piper damn well picked. Do you want me to continue?" He said, poking the man until his back was against the wall. "It doesn't get much better!"
My favourite Granny Weatherwax scene is her confrontation with the vampires at the end of Carpe Jugulum.