Do you ever watch "Ghost Hunters" on Wednesday nights? I do with my 2 oldest kids. I asked them first what they thought about it because I didn't want to open a door of occultism to them (getting into that stuff) or help them develop an unhealthy curiosity. Happily to my ears, they said: "Well, if there really is anything, I think it is poor souls in purgatory seeking prayers/relief...and, sometimes it could be demons, too." I was happy they learned well that there are not just "fun friendly spirits" to talk to and have friendships with as so many in the occultism world who are deceived.
I came across this article, "CHIEF EXORCIST OF MANILA OFFERS ADVICE AND PRAYER ON ALLEGED 'HAUNTED' PLACES" and was sure to read it. You can too, HERE.
He answers: How do "ghosts" jive with Catholic teaching?
He starts by saying it CAN be that there are haunted houses! "In scientific parlance," says Father Syquia, who directs the Office of Exorcism for the Archdiocese of Manila, "a house is said to be haunted when there are paranormal disturbances occurring within the vicinity -- invisible entities or beings manifesting themselves or making their presence known. Based on Church authorities and teachings, a 'haunted house' can truly exist."
So, if you enjoy watching "Ghost Hunters" but are not sure what to think about it...go read this priest's, chief exorcist, interview about it. :)