Paranormal Activity,
This movie was a first test screen from Steven Spielberg to see how people will react on seeing other normal household being attacked by a spirit/ghost and to see how scared you could be.
the movie was a big hit that paramount pictures desided to make this into a big movie, almost around the world people has saw this movie and they really said they where so afraid they had several nights with no sleep cause they thought they too had a spirit in their homes.

right now this movie is being released on dvd and was directed by Oren Peli.

However my pesonal thought on this is it aint scaring me as i saw this movie, must be since im more involved in this world as to paranormal.
so the movie did not do a thing to me as matter effect it had more clitches and wrong sets to let people believe spirits are bad.
i can tell you that is not true, spirits will not try to take over your body or any way to make you think they will. The only thing they most do is to let you know they are there and mostly they will do things to get your attention, and yes there are some spirits that might hurt you but also they too doing this to let you know they are there.

in most comen sence if you talk with your family around the table and start talking about they have to leave, in some cases they do.
i rather suggest seeing Ghost Hunters (also known as TAPS) From SyFy then this movie as it doesnt really explain where the spirit came from and why it wants the body of the female.

Synopsis:
After a young, middle class couple moves into what seems like a typical suburban "starter" tract house, they become increasingly disturbed by a presence that may or may not be somehow demonic but is certainly most active in the middle of the night....