I have a Samsung LN40A550 LCD TV, purchased in 2008. I have a 2011 mac mini connected via HDMI, and I use VLC Media Player to play tv/movies, most often x264/mkv files.
The native resolution of the TV is 1920x1080 so that's what I have the mac set to output most often, and I get video files with the same resolution whenever I can. However, often the video files I get are only 1280x720.
So my question is: Will it look better to leave the mac set to the 1920x1080 resolution, and then have VLC's full screen mode stretch the 1280x720 image to 1920x1080, or will it look better to set the mac to output a 1280x720 signal, and then VLC doesn't do any stretching.
By "look better", i mean picture quality and the shading / filling in of pixels, not frame rate or anything CPU performance related, obviously the latter would have less CPU load.