he bought this sony 50 inch wega lcd and has just regular hookups and no settings change. what should he do to get the best pic? he has a sony dvd player and an xbox hooked up to it with rca hookups ? will the quality really be that big of a difference with different cables? it was 2100 . it was an open box return i was told he could get a dvd to help him set it up, where and how much?