Wizardry 8 (first person party based RPG like Legend of Grimrock)
Neverwinter Nights: Hoards of the Underdark (best of the NWN games imo)
Final Fantasy 7 + 9 (get emu for 9)
Planescape/Fallout1+2/BG2 etc
Try the old Bullfrog games like Syndicate Wars, Magic Carpet, Theme Hospital, Dungeon Keep. If you like those then get Startopia (made by ex BF devs). Most ofthese old games are probably outdated in more ways than just graphics btw
For new oldschool games then Divinity: Original Sin, Grimrock, Pillars of Eternity, Shadowrun: Dragonfall DC + Hong Kong, South Park: The Stick of Truth, Dragon Age: Origins
Then you have hundreds of good adventure/puzzle games but don't know if anyone's interested in them