I've currently got it running at 1280 x 720 @ 50Hz, but text outside of Vista Media Centre is less than ideal.
The closest resolution via display properties on my HTPC is 1360 x 768. But when I chose this resolution, the only refresh rates available are 25, 29, and 30Hz. And when I do change to this resolution, I get a weird flashing type effect when changing between the desktop and Vista Media Centre, and for some reason my screensaver stops displaying my photo slideshow.
What should I be running things at to get the most optimal display in VMC and on my desktop when browsing the net etc? I do not play games so this is not a consideration (if it even makes a difference...)