Although there are “default” native resolutions, some games dont follow the rules, so its not 100% accurate unfortunately. Bear in mind some of those links in your first post show the res I wanted to display the output in, not the native resolution. For example I increased the GB to about 1.75 times the native size.
Jaguar
Max resolution – 800×576
ZX Spectrum
256 × 192
N64
240p (320×240), 288p (384×288), 480i (640×480), 576i (720×576)
PS1
320×240
Cave Story
320×240
Virtual Boy
384×224