What size plasma television should be purchased for viewing from six to fifteen feet away?
Assuming you're getting an HD set and purchasing HD programming,
here's the rule of thumb: The MINIMUM viewing distance is twice the
diagonal measurement of the set. For example, if you get a 42" set,
you should sit at least 84", or seven feet, away from it. Viewers
sitting closer may see the scan lines and other flaws in the
picture. If you're not purchasing HD programming, the rule of thumb
is to sit no closer than triple the diagonal measurement.