A Joke you CAN tell at work:
3 vampires walk into a bar. The bartender asks, "What’ll you have?" The first vampire says, “I'll have a glass of blood." The second says, "I'll have a glass of blood, too." The third vampire says, "I'll have a glass of plasma." “Okay, let me get this straight," the bartender says, "That'll be two bloods and a blood light?"

A Joke you SHOULDN’T tell at work:
An older man wearing a stovepipe hat, waistcoat and phony beard sits down at a bar and orders a drink. As the bartender set it down, he asks, "Going to a Halloween party?" "Yeah," the man says, "I'm supposed to come dressed as my love life." "But you look like Abe Lincoln." says the barkeep. "That's right, my last four scores were seven years ago."

A quick one:
Skeleton walks into a bar and says, “Give me a beer …and a mop!”

Jokes to tell kids:
What do you say to a ghost with three heads?
Hello, hello, hello.

Why did the witches' team lose the baseball game?
Their bats flew away.

Why did the vampire need mouthwash?
He had bat breath.

Who are the Werewolves’ cousins?
The Whatwolves and the Whenwolves.

What instrument does a skeleton play?
A trombone.

What's the difference between a ghost and a butcher?
One stays awake and the other weighs a steak!

Fun Fact: The mask used by Michael Myers in the original Halloween was actually a Captain Kirk mask painted white.