Horror Movie where a girl gets sucked into old Black and White Movie?

[in_vein]

I'm desperately looking for a movie i saw years ago when i was a child. It really scared me and i still got the images in my head and I'm looking for that movie since years! I only can remember one scene: Two teen-girls watch TV and one of them leaves the room. The other wants to switch the channel and suddenly the anchorman (?) tells her to chose a channel. She chooses an old black and white movie, i think it was a nice christmas movie with lots of people and a little boy - but all of a sudden the crowd turns to a killing mob with dark circles around the eyes and the little boy holds a knife and they all stab the girl. After wards - back in the living room - the other girl comes in and finds her friend stabbed on the floor.

I hope someone here can finally help me find that movie :/

[Unregistered]

poltergeist