'The Conjuring' is an extremely solid supernatural horror. I admit that I did find it less interesting as it went on, but even so I did comfortably enjoy seeing the progression of the story; I like that the plot doesn't majorly meander, each stage is clear.
It doesn't rely on cheap jump scares either, which is something I was expecting it to utilise. The supernatural elements here are very well done, we don't see terribly much of the demons, at least early on, so any appearances are effective. The stuff with the kids/mum is convincing too.
I was happy to see Vera Farmiga appear onscreen, I remember her fondly from 2011's 'Source Code' and have wanted to see her in lead roles since - she's excellent in this. Patrick Wilson and Lili Taylor are also notable performers, while Joey King has one particularly great scene.
I'd class this as more creepy than scary, admittedly I seldom find movies scary (just the way my brain is wired with fiction). I can obviously still sense when something is unsettling though, anything with kids being possessed does the job in that regard.
How this franchise has ten features and I hadn't even seen one is a mystery to me. Better late than never, hopefully this strong first entry is a sign of things to come.