edit: oh, oops this turned out long
I played through most of the King’s Quests(1,2,4+6) when the first cd-rom collection came out, which is a long time ago now, but recent enough that the first entries were already archaic. I still thought there was something enjoyable about them even if most complaints would probably also be valid. Lifting most of the story elements from fairytales give them a kind of innocent vibe and timeless quality, while they also retain the kind of casual brutality that pops up in fairytales, like a witch randomly appearing, capturing you and eating you. I remember being genuinely frightened of parts of KQ4 as a kid, though it likely wouldn’t work as well as an adult. There’s still something to be said for that I think, though It’s likely you’d have to be in a certain frame of mind to be receptive/appreciative of it. You’d also have to be fine with the clunkyness of the mechanics. I don’t know if I would be today. KQ6 is by far the best I think, and feels much more advanced and modern than the earlier ones. I remember it being much less stiff in tone and just having more personality than the others. I think Jane Jensen had a big influence in making that one.
The Quest for Glory games had much more personality and humour in general than KQ, though I only played the first two. They’re among my all time faves still. The second originally came with a physical map of mazelike alleyways you have to navigate, so that’s cumbersome to deal with I guess. What’s neat about them aside from everything else is how they straddle the genres of adventure and rpg in a good way. Maybe not terribly deep for someone coming from the rpg side of things, but still. It works well + feels (or felt when playing years ago) natural
Little Big Adventure 1 + 2 are just very likable for some reason I can’t pinpoint. They feel like of a time when a lot was still up in the air when coming to terms with action-adventures in a “3D”-space (isometric, but also a clean polygonal look). But also just charming and odd.
Marshmallow Duel was the only shareware game I ever actually registered, though imo the full version broke the game by overloading it with features. Functionally it’s like a stripped down Outfoxies. Two player only, with no computer opponent. The moveset and the weapons/powers of the unregistered version work really well together and gives a lot of room for play and surprising turns.
Elastomania/Action Supercross: Action Supercross(commonly originally referred to as across) was already a phenomenon with tons of fanmade levels before it changed name to Elastomania and seemingly got even bigger. I think the Trials series which gained popularity some years ago was likely patterned after it, but Trials went a more realistic route. Elastomania(or across) was initially most notable for the ridiculous physics that nevertheless felt internally consistent, sort of like a cartoon. The goal is much like the Trackmania games to shave seconds off your time, with hitting the quick restart button just as much a part of the process as anything else.
Ugh! (1992) is a pedal driven helicopter taxi game set in some combination of stone age/jurassic etc. eras. Again a game that plays a lot with physics. You carry passengers from location to location, pick up boulders to drop on trees for fruit/fuel or on dinosaurs to stun them so you can get a window for picking up a fare without getting rammed. There’s nuance that comes into play like maneuvering just right to get a time bonus while being careful not to knock into anything and lose a life; Landing quickly nearby a passenger being careful not to touch them and knocking them in the water(Being quick to land in the water so they can swim to your helicopter before they drown if you do); Building momentum enough to dunk the helicopter under a passage filled with water, etc. There a similar earlier game called Space Taxi that I haven’t played, but the physics of Ugh! feels very good.
The Commander Keen series are good, though the last three are noticably smoother to play than the first three. Keen Dreams is sort of an inbetween that’s still closer to the last three. The Fourth is the most diverse in environments and my fave.