That's tough; there's way too many great ones to rank them or limit it to five; any list of five I come up with falls short. I'll do my best.
Note: being jRPG discussion, this will only consider jRPGs, action adventures and action RPGs from Japan from my part.
1. Nier
2. Chrono Trigger
And now it gets hard as they're all so goddamn excellent.
3. FF VI (6)
4. FF IV (4)
5. FF III (3)
Ugh, this doesn't work. There's just way too many great ones. Mother, Earthbound, Chrono Cross, Lucid Dreamers, Radical Dreamers, P3/4, SMT Nocturne & 1, TERRANIGMA, Lufia II, SECRET OF MANA, EO, Seiken Densetsu 3, I could just go on and on forever and fill a paragraph with titles; there's too many to rank them.
Xenogears, Dark Souls, almost every FF game ever made, almost every DQ game ever made, Demon's Souls, every Zelda (pretty much), it's like a treasure trove of greatness. Wild Arms too, of course. Though first? I love the whistling.