Technically, the NeoGeo only has 1 resolution. All of the games have a 320x224 area, although some don't use the last 8 pixels on each side. If you go into test mode, then hardware test, you can get a crosshatch screen(white grid). Use your monitors position/size adjustments to make the edges of the square fit exactly on your monitor, then all of the games will be perfectly centered and use as much screen as possible with no overlap.