Baldur's Gate 1 and Baldur's Gate 2: Shadows of Amn
Best rpg's ever crafted. You can buy them easily enough as ten years later the games are still in print and being sold on store shelves.
Some rpg's boast a fantastic story, others amazing gameplay, some free-form adventuring and plenty of their visuals. But Baldur's Gate is the only series to have it all! The visuals, hand-drawn 2D isometric maps, are vibrant and crisp supporting even the highest of resolutions while subtle 3D effects make the art come alive. The combat is both fun and extremely tactical. And the story fantastic, especially the characters. Many of the characters in BG are considered some of the best ever crafted. Minsc & Boo even have their own website!
Add to all that the great mod community who've engineered a way to play Baldur's Gate 1 with the engine of it's sequel, Baldur's Gate 2, and who's refined an already amazing series to the fine cutting edge of perfection...
There just isn't another experience like it.