Retropie Arcade ROM quality

Greetings to all...totally computer illiterate newbie here!

I have managed to figure out how to download games (Golden Axe Arcade specifically)and add them to my Retropie. Trouble is, the quality of the games is poor...sound, lag, etc.

I'm also noticing that there are several sets for one game...am I in need of downloading all of them? I'm running the game via FBA (as recommended)...not that I know too much about what that is.

Thanks for any advice AND if this kind of topis is redundant.