Personally, I don't play these things unless I've only got a few minutes before I have to be somewhere otherwise I'd get nothing done. Warning! These can be addictive.
First off is an oldie but a goody - Halloween Hangman:
Well, I hope you enjoy the games. I wasted half a day playing, uh, pulling up these links. This last one is called Halloween Nightmare. I could play it all day. Hmmmm, maybe I will.