'Dawn of the Dead' (1978). It is perhaps the only zombie film which actually explores the epidemic from the very beginning whereas most are post-apocalyptic. Thus the way it shows the breakdown of human institutions and inevitable collapse of society is truly terrifying. It is like, where does this epidemic go from something distant you see on the news to something that is literally breaking into your home? When does it go from the same old routine of school and work to my only goal is now survival? Again, terrifying. 'Dawn of the Dead' is probably the most frightening film I have ever seen. It feels like one big nightmare, yet it is a nightmare that is a reality and does not go away.
Good question.. I've watched so.. (...) many.. ^.~
I've actually found that the "found footage" genre, seem the most real. Horror movies like [REC] and V/H/S (and the sequel) were pretty good. I also liked the Chernobyl Diaries, Afflicted, and Grave Encounters (both of them).
Oh, and if you know any good horrors with dead children, please do tell. ^.^
The original Amityville movies are great. My favorite is The Descent. The acting was great, I loved the all female cast which I don't think has really happened much in a horror film, and the back story of some of the characters.
The grudge, the original one, Ju-on the one based on real events before the americans ruined it with the sequal that never happened. Its cheesy but its a good cheesy like double Gloucester cheddar cheese
The Conjuring (haven't seen no.2., but I'm sure it'll be good), The Others, Suspiria, The Craft (even though it's not a horror at all), Insidious (only No.1) aaaand I can't remember any other which are really good.