[Kazilan]

Not too much more to add than whats already been said. Planescape: Torment is one of my top 5 games of all time. Don't worry too much about where you place your stats beyond some points initally in wisdom and intelligence, just build the character you want - I ended up playing through the game so many times to experience the various npcs and classes that it didn't matter too much. Constitution is also important in a number of interactions, as is dexterity. The only prerequisite for this game is that you enjoy a strong story, and can read through longer stretches of dialogue than you find in most other games. I wish more games were made in this setting.

edit - you know what, you don't even have to add a ton of points to intelligence over the other stats. It opens up additional dialogue, but as I mentioned you can utilize other stats (con and dex that I can think of, probably str too) in other types of interactions. The only one that benefits all around, in my opinion, is wisdom.