You won't be disappointed!
It all depends on your tastes
I personally love fighting games -- so if you want some suggestions, lemme know.
I know there are some other posts on the "best Saturn games" so browse through there.
But the "essentials" would probably be Nights into Dreams, Daytona USA, Virtua Fighter 2, Street Fighter Alpha 2, Sega Rally, and the Panzer Dragoon series.
Hope this helps.
Enjoy your 2D and [pretty good] 3D gaming bliss