Mine is the episode where it's the Lunar eclipse and Alison and Mike have the neighbours round for dinner, it's total comedy genius. Everyone talking around the dinner table while the ghosts dance round it chanting about the 'wondrous moon'
Mary: 'stew update, all the water has turned to clouds' and when the ghosts are watching Friends and Kitty declares 'I'm Phoebe, Lady Button is Monica and the Captain is Ross'