Selecting the correct HDTV size is important since you do not want to spend the big bucks for your HDTV and find that it is not the right size for optimum viewing.
With standard-definition TVs, the rule used to be that viewers would feel comfortable watching a set from a distance of 3 to 6 times the screen size in inches.
With HDTVs, the resolution is so much better that you can sit closer to a larger TV without noticing the pixels. So with HDTVs, the rule tends to be you can sit anywhere from 1.5 to 3 times the screen size (in inches) for the best experience. If you know the size of the room you have already, where you want to sit, and where your new HDTV should go once you get it, you can figure out the screen size you should buy.