Letterboxes on my LG 42" LCD HDTV...

Does it give any image att all and have you tried another data source, dvd-player and can i have exactly the numbers of your tv, like how old it is . The change that you have a panasonic screen is 90% and for me still the best way to watch tv, but is it just hd or full hd and what did you pay for it .gr richard

be sure you have selected the proper input on your TV; looks like you have an option of 2 HDMI inputs on the back or 1 on the side; or 2 component inputs on the back

Do you have an HD ready cable/satellite box? It sounds like your tv is displaying your games in a resolution lower than what it can handle.

you need to bring your LG 42LC2D 42 in. HDTV LCD Television to tv technician the problem is on boad

HD ready = the tv is capable of processing and displaying HD signals 1920x1080 on its screen that has a lower native resolution 1366x768 
You cannot change that, the tv is build that way.

Not sure about your exact model, but for most HDTVs, you cannot set the resolution in the TV itself, the TV will automatically adjust to whatever signal is sent to it.

Note that Many HDTVs cannot do 1080p over component video inputs, only HDMI. Also, check for firmware updates for your TV, as manufacturers seem to be are often fixing bugs with things like HDMI input detection and so forth.

You unit should be under warranty. contact the manufacture for the nearest authorized servicer.

Try running a set of audio cables(Red/white) from your audio out jacks on the back of your TV to your reciever's audio in? 

take it back to where you purchased it and get it exchanged.

check to see you have the cables required by the tv. usually you need hdmi or dvid for hd display. digital rights management protocols have resulted in chips in playing devices that allow only the use of the referenced cables to protect content from being copied. in some sets they default to not playing in hd, but still play something.
look there first, otherwise you may have an input source mismatch. follow instructions on the dvd player first, then make sure the tv has compatible settings.
if that does not solve, you have a service issue with one or both.
good luck
mark