You can choose any night light to protect you from all of the ghouls that come out after dark, but I would suggest this DC Comics The Flash Night Light.
The reason is simple. The Flash can run faster than any living man, so he can chase down any ghost or ghoul easily and protect your room during the dark hours.
Let the Flash protect you for just $18.99 from Entertainment Earth. Pre-order it now and it will be available in March.