Ultima V - A totally non linear RPG way ahead of its time. This one kept my occupied for literally a year of hardcore playing on my Apple II back before the time the ADD generation and www.gamefaqs.com. The story is amazing even with only 3-10 lines of dialogue per NPC. Although back then, story was all you had to sell a game. The "stunning graphics" sure as hell didn't
I would highly recommend playing through this one, and if you can't stomach the CGA graphics, try the remake. Just do a search for "Ultima 5 Lazarus" and you'll find it, it uses the Dungeon Siege engine. Defiantly of the best remakes I've ever seen. Ultima 7 deserves an honorable mention here, though not nearly as compelling as Ultima 5 IMHO. God damn you Voodoo memory management system! What do you mean you need 590k free to run w/ sound and mouse?! I've only got 640k total!
Defender of the Crown - Ahh, I miss this one for the old Amiga. Nothing like Jousting, freeing maidens from their captors, and having them show you their undying gratitude in bed
Final Fantasy II & III (U.S. 2 & 3) - The pinnacle of the final fantasy series IMHO. Although FF7 and FFX (not X2) have honorable mentions here. Great examples of "Epic" stories, truly a staple in the fantasy game genre.
Warcraft - god, what an awesome game. If someone were to ask me if I would want back the months of my life I wasted playing this game over Kali using the IPX/SPX protocol, my answer would be hell no
What an experience.Doom - Of course this is in my top 10, this game started the FPS phenomenon. I know Wolfenstine came first, but this one was the one that really sparked the new genre. Unfortunately, we've had to deal with years of terrible "doom clones" as a consequence.
Planescape Torment - The pinnacle of the Infinity Engine series IMHO. The story portrayed in this gem of a game is a contender for the "best story" out of any game I've played... "What can change the nature of a man?" Oh so many things, you'll find, if you've played through this beauty more then once
Fallout - Hands down, so many decisions, so little time, so many heads exploding like ripe melons. What more can you ask for?
Diablo - This one deserves a mention here just due to the sheer amount of time I spent playing this bugger online. I have this one to thank for my stunning 2.0 GPA my first year of collage. But... the cat5 connection right in the dorm room made it hard to resist. **drools** High speed internet in an age of dial up, I was a god among mortals online
Worms - Nothing like cute little worms dressed in army fatigues using weapons of mass destruction to annihilate each other. I played this one a lot with my room mates after collage over our townhouse's LAN.
Oblivion - Good story, awesome improvements in the combat system over Morrowind. However, I didn't like the little arrows pointing you exactly where to go on the compass, nor did I like the watered down Morrowind game system. This one had a lot of negative points to it, but it also reintroduced many things that I find are absolutely integral to RPG's such as a high level of world interactivity, complete freedom from the main plot, allowing you to explore the entire world as soon as you start the game, and believable NPC schedules (one thing which ultima 5 had years before by the way, why they got nerfed into pretty "text blocks" standing still for all eternity until now is beyond me)
Ultima Online - This one here deserves a mention because it also created a new Genre. Still to this day, IMHO, one of the best MMORPG's on the market despite its outdated graphics even after 2 graphics overhauls. This one had so much potential... wana be a shepherd? Sure, no problem! wana' be a blacksmith or tailor? Sure, no problem! wana be a baker who moonlights as an orc slaying adventurer? Sure no problem! I'm a firm believer that EA killed this product, which would have been way cooler if Richard Garriot actually played his character "Lord British" like he originally intended and created DM run story arcs.