One of the earliest was my dad bringing home a Packard Bell with Windows 3.11 (for Workgroups!). It came with a bunch of 3D multimedia games, like 3D Body World, Undersea Adventure 3D, 3D Dinosaur Adventure, and some game based around Speed where you could "ride" a virtual roller coaster (basically meaning you saw some POV CGI animation). There was something really fascinating, yet completely unsettling and alien about the games. Like many of them featured some incredibly basic raycaster portions where you would wander around rooms that were supposed to represent the inside of a human body or the ocean while this eerie MIDI music would play. There would also be spoken dialogue and stuff too.
In the 3D Body World game, you were basically microscopic and had to run around a person's internal organs, zapping out any infections they had. If you fucked up, you could kill the patient. Strangely, too, I remember that you could run outside of the hospital before choosing a level but there was nothing outside.
I think this intro where the man walks behind the X-Ray is the first thing I actually saw on the computer. It spooked 5-year-old me
Here's a taste of Undersea Adventure
Here's an animation of a dinosaur chase from 3D Dinosaur Adventure that I probably watched at least 100 times as a kid
Same with this one where a T-Rex is reanimated and goes for a run
And don't get me started on the Grolier Multimedia Encyclopedia Release 6