Hey, i need help with a Render problem

[PROBLEM SOLVED]

Hey peeps

as the title says i am in need for answers about a rendering issue i have with Cycles render in Blender
[Thus be advised that i am fairly new to 3D modeling and blender is my first attempt in this area!]

So on to the problem.

My final render have ALOT of noise/grains/fireflies, but my prerender is almost perfectly sharp. why is this?

[Picture]


I would appreciate it ALOT if anyone you fine gentlemen with alot more experience than I could tell me why?

[Link to .Blend file]
http://sharesend.com/02h5nqvz

[Know this]
i have tryed many tutorial to try and clean my final render thus none have worked.
i’ve tryed to clean up after all these failed attempts but there might still be some uncleaned stuff around

Thank you in advance

This is somehow new - Layer Samples overrides what is set on Render tab Samples panel: in Scene Layers you have set 2 and on Render tab Use is chosen from dropdown.

ooooh yeah i see that now. didnt know it could do that.
Thank you eppo, your help is much appreciated!