The Witcher: Enhanced Edition is the most underrated game ever.
It's perfection. The graphics are amazing: if you compare with Dragon Age they are so much better even though this game is older. The music is a masterpiece and fits perfectly everywhere ... it really makes you feel like the places actually exist and gives the game a very unique and special feeling. The characters are very interesting and you want to know more and more about them all the time (very much as in Baldur's Gate II: Shadows of Amn). The story is also awesome ... I don't want to spoil anything but it really is great.
If you like RPGs then buy this game. It's a masterpiece and one of the best RPGs ever made (Baldur's Gate II and Morrowind are the only RPGs I recon beats this game).