I'm not much of an RPG player, but:

Fallout[1/2/: New Vegas];
If you can deal with its endless random encounters, EarthBound;
Undertale

Oh, and can't forget the Yakuza games. They are more tenuously RPG in general, putting more effort on the brawling side, with the exception of the newest game, Yakuza : Like a Dragon, which is a turn-based party type one.

Candybox and Candybox 2.

>console FPS-RPG hybrids
* STALKER SoC / CoP
* Vampire the Masquerade: Bloodlines
These are both a bit janky in their own ways, but atmospheric beyond words if you're lucky enough to make that emotional connection. They nail that feeling of coming into the world as a nobody and the satisfaction of learning to deal with strange situations. There are various 'unofficial' patches/mods around of varying quality, ask more if you're interested. Oh and how could I forget..
* Deus Ex

>90s style RTwP
*Baldur's Gate 2 is the classic of this genre
*Arcanum & Planescape are a bit more creative, and personal favourites of mine
but right now I'm loving Pathfinder: Kingmaker, it's a fresh take on a pure high fantasy romp. Character creation options overwhelmed me at first, so I made a pure good guy paladin; from this angle the content is very satisfying but I'm keen to go through it as a selfish dickhead and enjoy all that sweet, sweet reactivity I think is there

>linear turn based JRPGs
* Shin Megami Tensei: Nocturne (released here as Lucifer's Call) can be found cheap for your old PS2. The game's (relative) brutality might put you off but it's the pinnacle of the genre for me. There are various other games, by the same developers, in the same vein, that are a bit simpler and more often recommended to newcomers. Like Digital Devil Saga, maybe a Persona game (which revolve around tedious delightful cringeworthy creative high school relationships content)
* Dragon Quest games (powerhouse in Japan) have a less interesting combat system and a more traditional setting. More classical fairy tale style, which may be fun escapism. Play if you want to live in world where the good guys always win in the end, there is always a magic harp to wake up the sleeping princess, and no person is truly evil, only misguided/manipulated and redeemed in the end

Also everything >>24039 said.

>>24043
How could you forget System Shock under FPS.

>>24044
I guess you could say it'll be a shock to his system when he realises he omitted that one.