Haven't seen Insidious but Home Movie was probably one of the best 'recent' horror films I've seen in a while.
For a small taste of Japanese Horror, there's these shorts.
I found a lot of Faun No Tane(manga) stories to be creepy.
I like Halloween(Original), Psycho(Original), The Devils Rejects, The Texas Chainsaw Massacre(Both), The Strangers, and various other films but I don't know if they will scare you OP. A lot of horror these days is more so about gore than actually getting inside of your head and presenting an idea to you that can freak you out to the point where you stay up at night and think about things that could happen to you if you turn off your lights. That's scary. That's the type of stuff that scares me and just generally freaky and out of place things in everyday life. Right now typing at the computer if I turned to my right and saw someone standing outside looking at me through the window it would freak me out. Because something like that is so random and it could happen easily. Person probably wouldn't even wish harm on me but the idea of someone watching you like that is creepy.
How long had they been watching you?
Why were they watching you?
Who was that anyway?
Bunch of questions would immediately come to mind. Doesn't have to be a bunch of blood and guts to be scary.
But I digress. Japanese/Korean horror is usually pretty creepy. They build up to the scares and create a mood throughout the films where things just feel tense and uneasy. I like that in horror films.