Can not get my hd channels to work. other tv in house also with hd channels works fine. regular channels working but the hd chanels are not working. not sure what to adjust or why.

You can't change the resolution on the television itself. You change the resolution on whatever you have connected to the television. Let's say it's a cable box or a blu ray player you've got connected to the television. First off you have to connect it to the television with a component (green, blue, red, white, red) cable or an hdmi cable. Then you make sure it is only connected to the television with either a component cable or an hdmi cable. This may sound ridiculous but there are some people that have their cable boxes and blu ray players connected to their televisions three different ways ( an hdmi cable, a composite cable, and a component cable) when they only need to have it connected one way.
Select the proper input on the television. Set the cable box or blu ray player's resolution to 1080i or 1080p (in the case of the blu ray player if it the tv will allow it).