This page will have information and advice on selecting a TV and other video components.
Well, OK I can save some time when it comes to selecting a new TV… Buy a screen which is larger than you think but remember the showrooms are large and your living room is not!
These days this will almost certainly be LCD based with an LED backlight. When in the showroom look for screens with a wide viewing angle, where blacks look black but you can still see detail in dark sections of the image.
Look for models with high refresh rates (200Hz or above).
If you are considering adding a home theatre sound system then ensure there is ARC (Audio Return Channel) support on one HDMI connector!