TV PICTURE QUALITY

I am thinking of upgrading my TV. Currently set up to Sky HD system with viewing card. It has HD channels, but I cannot see any difference between normal BBC and BBC HD.

When I go to Carrefour they have these TVs on display with magnificent pictures almost jumping off the screen. If I buy one will it be like that at home connected to my Sky box?

Wait until a football match is on, watch it for a few moments on normal TV, take note of the crowds faces, they would be slightly blurred due to the distance, then switch to same channel but HD, the crowds faces should look very clear and distinctive. The wild life shows should be so much better in HD as well.

In the shops that sell TV's they / many of them, use a system for demonstration purposes only just to sell the TV, forget the name of it but google it and it comes up.

All a bit of a catch at the moment like the supposedly 4K thing.