i always advice people to go buy or at least compare television and computer screens in a store. no matter how good they try to explain the quality of the image the only way to really compare them is in real life (you can always buy the one you like from an online shop)
btw if it's only for watching some movies and playing some music, wouldn't you be better off with a projector ? it costs as much as a tv screen, but it really takes watching movies to another level.
(this one seems quite good for $800 http://www.newegg.com/Product/Product.aspx...82E16889106017)