Mint would probably be the safest bet. You could also take a look at Manjaro XFCE, though Manjaro is a bit more advanced than what it sounds like you're looking for. There's also Zorin OS with their "lite" version which runs a modified XFCE that would probably work for your needs.
However, if you go for Mint, I'd definitely go for XFCE. I've never used labwc myself and I'm more of a Plasma guy, but XFCE is, in my own experience, a very good DE for a low-spec system. With the increasing spread of Wayland, I wouldn't be shocked to see Wayland support on XFCE in the future. Cinnamon actually has an experimental Wayland version and it's not as resource-heavy as some might think I have a 2012 laptop running Mint Cinnamon and it runs surprisingly well on that system. Then again, if you're just going for a minimalist installation, it's not necessary.
I began with Morrowind and I've played every TES game (other than those obscure "Travels" games in the early 2000s) but Oblivion remains for me. That said, Daggerfall's sheer scope in both gameplay and world size is incredible, and Morrowind's perfect blend of sandbox freedom with an awesome plot definitely do make them candidates as well. I just personally love the entire series and Oblivion was the one that converted me from "fan" to "megafan" so that's why I go for that one.