Best beginner Raspberry Pi retro emulation: ROM legality and SNES/Genesis.

[JohnB]

I've been wanting to set up a retro game emulation system on a Raspberry Pi to play classic SNES and Genesis games, but I'm a bit overwhelmed by the options. I've seen RetroPie recommended, but I'm unsure about the legalities of sourcing ROMs for games I no longer own physically. What's the best beginner-friendly software setup, and are there any reliable guides for configuring controllers and optimizing the video output for a modern TV? I'm also curious about the performance limits of a Pi 4 for more demanding systems like the Nintendo 64 or PlayStation 1.