The important thing on resolution is that the LCD has a native resolution that your video card can output and your setup can handle at a decent FPS. Wikipedia has a good example of using a non-native resolution here:

http://en.wikipedia.org/wiki/Native_resolution

Also don't overlook what inputs the TV has. If you are using for HDTV also you are going to want 2 DVI inputs or 1 DVI and 1 VGA. Just make sure it has enough for what you need as reaching back there everytime you want to change the input is really a pain.