Open world, I like Oblivion and Skyrim, Morrowind was just too dated for me to enjoy, and I'll throw in fallout new vegas for story open world games.
Otherwise I'd say Euro and American Truck Simulators both a pretty decent games, if your going ETS, I'd throw the Promods map as a must have, i feel it far superior to the base game + DLCs, though you do need both to use it. ATS began later than ETS and I feel likes it's on a whole far more fleshed out being able to take the lessons from ETS and use them from the start, but the quality between NV and CA and the later states is massive, WA, OR, NM and AZ are quite a bit a head of the two base states but I think they will bit by bit improve and rework those to states. You don't do much but drive from A to B but it's enjoyable and pretty beautiful even on the low graphics I have to run it on. I think UT will be released around the end of the year, and hopefully they can can get Idaho done to just to box out the map and ease the corridor driving feel to it. Also I believe the promods team are working North of the border.