Some of my favorites:
1. The Warlock of Firetop Mountain - I loved this one so much that I converted it to D&D mostly so that I could map out the exact floor-plan. Realizing that the Warlock has no easy way out that didn't involve wandering through a bunch of madly dangerous rooms, I gave him a back door, high up in the mountain, which was how he brought the monsters in. It was like a kind of zoo-arena, where he'd train them up before placement in the larger dungeon.
5. City of Thieves - the most dangerous shopping expedition in the world felt like you were in a real place.
6. Deathtrap Dungeon - having it be a competition added some amazing tension, as you were always wondering where your competitors had gotten to.
11. Talisman of Death - had such a rich world to explore, which was fully realized in standalone series Way of the Tiger.
13. Freeway Fighter - way better than Beyond Thunderdome is this Car Wars style post-apocalyptic adventure.
22. Robot Commando - every time you find a new mech you get an interesting decision, weighing up the pros and cons.