In "The Lottery," is there significance to the names of the characters?
The characters in "The Lottery" are mostly named with simple, folksy names; no one has an overtly symbolic name, save for Old Man Warner, who represents tradition and history. His name is a nickname, though, as he would only be called "Mr. Warner" and therefore have little symbolism. Mr. Graves could have symbolic merit, as he helps to officiate the ritual that ends with the winner in a literal grave, but this is not in the text and must be extrapolated.
One character who could be said to have overt symbolism to his name is Mr. Summers, who oversees the lottery; since it is, at the end, a harvest sacrifice, Summers represents the growing season of summer, after the crops have been laid in. He keeps the crowd under control and makes the lottery accessible instead of horrifying; in this manner, Mr. Summers represents the meaning of the tradition.