Can anyone help me?

[beware]

I seem to get over compression with directv from time to time as is evident when characters are outlined when standing in front of a dull color background. I recently putting my sharpness setting down to 45 from like 50 for my blurays to look better. Some have suggested I lower my sharpness more because it adds noise.

if I have a Vizio 46 full LCD HD TV, what should all my settings be or better yet what should sharpness be on for best picture quality? I never noticed it before directv and I have had this tv since 2009 so I am late to the game.