Render is incredibly Grainy! I'm new to blender and I started last week. I'm now having trouble with the final results of my render, it looks incredibly grainy.


What I have tried so far is that I changed the resolution to 100% , samples to 500, tried using the 'area light' and i enabled 'multiple importance'.

Here's the link to my Blender file: 

UPDATE

I can't find the AA settings:



Update:
When I try to render my animation it comes out as nothing.


It also says this:
Probable causes of noisy renders:
(click on the links in blue)


Render Samples set too low 100 samples might just be too low for what you want, try a higher value.

Here's the scene at 800 samples:


Samples set on render layer override regular sample settings.
Lights or environment not set to multiple importance. Aditionally this link
render resolution is set to less than 100%
Use branched path tracing instead of the default samples



Bring up the AA samples and then set the values for each type of sample according to the materials in your scene. Note that each of this values is multiplied by that of the AA Samples. (for example 4 diffuse will turn into 500 samples when the AA value is set to 125)