So here's the thing with Dragon Quest. The most recent game is DQ11 which is out on all current systems. And it is really, really good. They totally nailed it.
There are very good remakes of 4, 5, 6, 7 and 8 on the DS and 3DS so all of them are very approachable. Dragon Quest 9 was a DS game. 10 was a Japan-only MMO. And then the first three games are pretty easy to find if you develop an interest in the series. And unsurprisingly they are good. But they are noticably older in style and execution.
You can expect a trditional turn-based JRPG experience that plays upon classic series tropes and ideas. The joke is that every Dragon Quest game is more or less the same game every time but they still manage to make it great. You can play any of them and have an excellent time assuming you enjoy the style of gameplay. It is worth knowing that these are long games... especially 7. And there is always a lot of post-game content as well as battles and challenges for nerds that decide to max their level and get all the best equipment.
Given the question you asked, I would start with the newest game which is DQ11. From there you should probably choose between DQ8 or DQ5. 8 is very popular and brought a lot of new fans to the series, plus it is great. 5 is probably the best game in the series but we are talking a difference of inches and not miles between games. My personal favorite is DQ7 because it keeps going and going. But yeah, everything from 4 to 11 is great, you really can't go wrong. The weakest of the bunch is 9 because it is too easy. And unless you speak Moon, you can ignore 10.
We also have a
DQ thread on the forum. Remember that DQ is popular because it is traditional. Sometimes you will see people complaining about basic story and predictable archetypes and boring fantasy settings with castles and dragons; those people are missing the point. The game is loved because it still tells a classic sort of story with traditional gameplay and it does those things really, really well.
Here we go, this is the image I was looking for. Of course it was on the first page of the DQ thread and I started on the last page. It is missing newer games but sums up the series pretty well.
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