It's a common predicament. You spend tons of money on a shiny, new HDTV set, only to get it home and find super intense colors and a blindingly bright picture. While this might look cool for about the first two weeks, it's like listing to all your music with the bass and treble controls all the way up, and the loudness switch on. It gets old after a while. You want to listen to the music the way it really sounds and see the TV picture it's supposed to look.
The reason your TV is so ridiculously intense is simple. Most stores use super bright lighting. While this is great for everything else, TVs are best viewed at normal or dim lighting to look their best. As for the intense color, manufacturers do it to catch your eye. Kinda like turning the bass up on speakers in the store.
Go into your TVs menu, find the picture mode, and set it to "normal." Sometimes the default picture mode is "demo."
Now that you've got the TV relatively on track, it's time to do some more advanced setup. Look through your DVD collection and find a disc with the THX Optimizer. Try an episode of Star Wars or a Pixar movie (I used the one on Monsters, INC.) Make sure you do the setup in the same lighting conditions you'll be watching TV and movies with.
Later, I'll get into the service menu.