Obviously, Dragon Quest 6.
Nothing against the original Super Famicom version, who is released only in Japan but avaliable to play with english patches on emulators, and get a huge sucess who continues today, but the DS version - in my opinion - can be the definitive version of the game, like the GBA version of Final Fantasy 6.
In the time of the release, in both Japan and the West, Square Enix done few modifications for the DS version, with few of them don't made fans happy. One of the small disadvantages of the version is the removal of recruitment of the specific Infamous Monsters with the Monster Master Vocation(who appeared in other variation, called Monster Wrangler, on the R HD version of DQ3). In the Super Famicom version, only few of them are recruitable due for the RAM of the cartidge, but the invited ones dones more fun and variation of the game, but on DS version is not possible to have one Infamous Monster because there none of them and in their place is added the Monster Buddies, who is recruitable as separate characters and all of them can be inserted into Vocations, giving more time to grind them in every Vocation(as the Buddies also can't be Hero, like the other besides the protagonist). Majority of these Monster Buddies are from The Slime Family. The other disavantages is no other than the english version, who continued with the localization of some names into others with few funny verbs, and becomes a tradition of the metaseries today(even on Dragon Quest XI S).
But the greatest vantage of DS Dragon Quest 6 is the inclusion of the Party Chat option, as the US version of DS DQ4 strangely removes this. But be ready for humorous dialogues!
The Dragon Quest 6 on DS is created on the same right to fun as the GBA version of Final Fantasy 6. With easy adjustements, a small increase of difficulty, and the use of Zoom between the two worlds(is all of them are half explored), the recreated version is better than the original, but the version is not perfect due for the mentioned disavantages.