40 – 46 Inch Flat Screen Tvs That Don’t Require Hd Signal To Function Properly?

I’m looking to buy a new LCD tv between 40-46 inches that does not require an HD signal. I am having a hard time finding TVs that fit this requirement. It would be great if I could have a few suggestions.

What Actual Function Does A Hdmi Cord/wire Serve For Flat Screen Tv? Specifically A Plasma Tv?

Is it absolutely necessary?

Samsung Flat Panel Lcd Tv Screen Totally Black On Any Input But Audio Continued To Function?

I have a Samsung Flat Panel LCD TV and recently, while using the tv, the entire screen just went black. The audio continued to function but even when I change source or channel or anything I can’t get the screen to show any kind of picture. I’ve had the tv for prob. just over a year.