Here is an example of a blurred background...I am "forcing" you to look at Hannah and Cayden. If everything was in focus, it would be such a busy picture you wouldn't know what to look at first. A blurred background guides your eye. ;)
Can you notice how the wall looks grainy? (Taken with an iphone) If I could make this really large it would become even grainier or more "pixely" (the resolution is low). The switch to black and white helped, I think (In the least it got rid of the yucky yellow color !). I also used my de-noise option in editing which can help soften a grainy pic.
