How do I deal with bad Roms I was playing a super Mario 3 ROM and noticed that on the left side there is a light blue all along the side of the screen that don't seem to be normal also there is some clipping on the bottom right and right side of screen edge ?

/ NES ROM super Mario 3/ Have you ever came across this before in this ROM or any other ROM ? How did you fix this is it an emulator issue or a bad ROM

Also how do I find the best Roms

I've downloaded over 700 NES Roms and I now wondering if I have a group of bad Roms