Just going to comment on a couple of the games that I have some familiarity with:

DOOM was an instant classic, but the reason the original trilogy (DOOM, DOOM II, Final DOOM) still has staying power to this day is because of the modding community that sprouted. Try playing a custom map megawad along with the Aeons of Death weapons/enemies megawad in a DOOM II source port (e.g. GZDoom) -- hours of fun times are ahead.

Secret of Mana was a fun action RPG to play in its original form on the Super Nintendo. I've heard that later ports of the game were not so good. But it was the sequel, Seiken Densetsu 3 (which to this day still hasn't received an official release in the U.S.) that is considered to be the masterpiece of the series.