Chrono Trigger
Final Fantasy (of older releases like VI VII VIII IX X)
God of War (the OG version, may require PS2 emulator*)
FreeCiv
Touhou
Other than that, any PC game older than 2010 should work.
If you want to play console games,
RetroArch can emulate everything from PS2 and PSP downwards. But from
MY experience, I suggest using
PCSX2 for PS2 games ,
PPSSPP for PSP games,
ePSXe for PS1 games and RetroArch for anything else (SNES and stuffs).
If you think old console game graphics are bad, upscaling your game may work. But the performance is questionable at best.