1) Secret of Mana (SNES) - This is easily my favorite RPG, since it's real time combat and supports 3-person multiplayer, in addition to being a great game. And whatever you do, do not confuse it with that POS Legend of Mana for the PS.
2) World of Warcraft (PC) - ranked so high because it's currently devouring my soul. Should the gods of coincidence smile upon you, say hi ( or give money xD ) to Shadowtwist on the Eldar'Thalas server sometime.
3) Vampire The Masquerade: Bloodlines (PC) - First game to make use of the HL2 engine following it's release. It's really rough around the edges, but if you're into the WoD roleplaying system, or think you would want to roam around as a vampire, you need not look further than this one.
4) Morrowind III (PC) - the openendedness is amazing, it doesn't get much more freeform. Probably the most replay value you'll get out of any regular single-player experience.
5) FFVII (PS) - the first one I played, the first one I beat. Still stands above the rest at the peak of the FF series, IMO
6) Chrono Trigger (SNES) - another square masterpiece. Genious battle system, and a great story to boot
7) Neverwinter Nights (PC) - simply because of the fact that the replay value of this game will never decrease, because of the easy to use toolset and willing fanbase