I want to put a display on the wall and stand five feet away with a keyboard and mouse while working (mostly Emacs, web browser, and reading pdfs). What should I check to determine whether a TV would work well in this configuration (without overscan issues and the like)? Is the only safe thing to go to a physical store with the computer, set everything up, and check for artifacts?
This is probably most dependent on the video card and drivers that you have available. A good video driver should allow you to adjust things such as the overscan %, centering, etc. to get the best picture possible.
I know from experience using an LG LCD TV with Windows 7 and ATI graphics that all drivers are not created equal. I was forced to downgrade my graphics driver when ATI decided to remove overscan settings from more recent releases. That being said, there are drivers out there that allow you to mold the picture to fit your screen.
Your best bet would be to get a high resolution PC monitor and just use that. The monitor will have much better quality for computer use. If you must get a TV I would say the primary concern is what your computer is capable of, more so than the TV.
The reason that a TV seemed attractive is that I could get a 46" TV for about the same price as a 27" monitor, thus letting me work from a step further from the display with similar perceived pixel/display size.
