If you are going to use it for watching TV then I recommend you'll consider a Plasma screen and not an LCD screen. Although some people will tell you that Plasma is old technology I think that LCD technology is not to mature and larger screens do not show TV so well.
I heard that Toshiba has good 42'' LCD screens.
For a Plasma screen you can choose between Panasonic and NEC which are the best Plasma companies today.
Go to a proffesional cinema theater shop and look at some screens. They will also give you some good info and will find a specific screen for your needs.