Roleplaying has at least two disparate meanings now. It is used [erroneously] to mean job-play, as well as (the correct meaning) personality play. In the first instance some people associate "Tank" as a —role— as a service/function of a fighter. The second instance in this case is that of playing the specific character. One plays the role of the fighter... like Minsc for instance, or like Montaron [both of Baldur's Gate], and both very different roles; different ethics, goals, and moral limitations.
In Planescape, the Nameless one can be of any class [job], and can change classes throughout the game, but the role is always that of the immortal wanderer, and his inner demons; what his personality is like at the time of play. Play is extrapolating what he would do in the given situations.
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With the above said... Legend of Grimrock is a good choice of non-RPG.
There are zero roleplaying choices in the game; you just explore the map, and kill monsters. If one thinks that names, hit points, and leveling up makes an RPG... then consider that Myth:The Fallen Lords has all of that, and is in no way considered an RPG.
In that respect even DemonStone might qualify as a non-RPG—and that's a D&D/TSR product.
**One aspect for many seems to be that RPGs must allow custom PCs—or they are not 'roleplaying'. It's BoguS IMO. So long as there is a given role [be it custom, full, or partially defined], it has the potential to be an RPG; has the potential to act in keeping with the character. Planescape is arguably the best RPG, and it has a fixed character. The Witcher is a damned good RPG, and has only Geralt as the PC.
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Honorable mentions [non-RPGs]:
- Overlord (series)
- War for the Underworld
- Shadow Warrior 2013
- Homeworld Remastered
- Styx--Master of Shadows (It could have been an RPG if they so chose.)
