I press F12 to render the camera view, but I just get a pixelish version of the render.

Can somebody tell me how to change that? I have already changed the object's "Render" Resolution to 100%.
Well, I have something to report now: When I use the middle mouse button to scroll out a little, the render appears a little smaller (seemingly at 100%), and it looks the way I expected. However, I wonder why that is that the render appears at like 125% for me instead of 100%.