For me it was.....

Nightmare On Elm Street

Evil Dead

Texas Chainsaw Massacre

The Omen

IT

Dracula and


Halloween

It was 1918 IIRC, but I don't see the point in narrowing it down to 1960's and on if we're talking most influential

60's- Night of the Living dead
70's- Texas Chainsaw Massacre
80's- Nightmare on Elm Street
90's- Silence of the lambs
00's- Dont know yet, but i really like the whole Saw thing.

60's- Night of the Living Dead
70's- The Exorcist
80's- Friday the 13th
90's- Dead Alive (if it even came out in the 90's). If not, then Hellraiser.
00's- Saw

60's - NOTLD
70's - TCM/Halloween
80's - Evil Dead
90's - Blair Witch Project (Scream may have spawned more imitators, but it was backwards referential, whereas Blair Witch was a forward step into the digital era)