Settings to optimise display

[Keylonta]

Hi, I've been trying to test the different video settings from the Quick Settings options, e.g., Max Scaling, Correct Aspect, 692x540. And also the Keep aspect ratio when scaling option in the Video settings, etc. but I can't make sense of it all, e.g., Full Frame was the only setting that didn't crop any of the image (I tested this on the first screen that appears when starting a game), but when playing the game, the game window is really small on the screen. Auto fixes this but introduces cropping on the first screen mentioned above.

What are the exact settings needed to make games keep their original aspect ratio (or a more suitable aspect ratio) but so that all images take up all available room on the screen with no cropping?

Once I know how to do this then I can just toggle between Fullscreen and 1:1 when needed using the option in Arcade.