Best RPG is without a doubt Baldurs Gate II: Shadows of Amn

If anyone here has played this game, you'll know what I'm talking about

Great gameplay, engaging storyline, tons of classes and subclasses (first time I played through, I was a Bard whom I got to level 21, second time through, a Mage whom I also maxed out). It also is a plain huge game. I spent hours and hours playing it, and I still don't think I've completed all the side quests, of which there must be at least a hundred. Mind blowing

Another great RPG is Neverwinter Nights, which is a lot like Baldurs Gate II, but with better graphics, more class options and other cool features. Only bad part is you can't have a big party like in Baldurs.