@Harry Potter For Stella, you don't like these colors on Stella, you can adjust palettes to match your likes
Options > Video & Audio > Palettes. Palette: Standard, z26, and Custom. For TV effects, TV modes: RGB, S-Video, Composite, Bad Adjust, and Custom. Also for Audio, you need to adjust audio too...
@Wizzard How fast or slow you can play these games
Options > Emulation. Adjust emulation speed between 0 and 1000% (The default is 100%)
Hope it helps..