I swear I've found this one before, maybe on another site. Somewhere between 1988 and 1992, my brother was allowed to borrow an IBM PC from the school (it was an anti-theft measure). I remember we played Hack (predecessor to Nethack), Brøderbund's Ancient Art of War, and a Hoyle card game. There was also an RPG, set in space. I don't think I ever played it myself, but I watched my brother and his friend do so. I remember there was a scene where you surprised a woman in a shower (nudity covered with a shower curtain) and there was an (optional, I think) encounter with a dragon. I remember that because my brother's friend was showing how to cheat to get the best equipment, which barely sufficed.
In my memory, the graphics were in vivid color and highly detailed, but the odds are good they weren't as awesome as I remember, since most games ran off of 3.5-inch floppies (although the computer had a hard drive), and the RGB graphics card was a major upgrade over the standard EGA.
Buck Rogers: Countdown to Doomsday comes to mind, but what I've found doesn't match up with my memories. Although, confounding this, I found a TV Tropes YKTS question where I was asking after this, and accepted Buck Rogers as the answer... I still can't find the two bits that I remember so vividly.