Although YOUR images are never really affected by a resize, no matter what resizing reduces (mathematically) an image's detail. And also, locking into a screen's aspect ratio might limit your art, your "shot"... If anything, it would be best to be locked into DPI modes. Just make your picture, don't even bother lowering it's resolution! Some of my rigs are at 800x600, some are at 1600x1200. But the average is closer to 1024x768...