I just beat Never Winter Nights 2, and I feel like starting planescape. I have always been turned off due to the AD&D rule set but I decided to play it anyways. I do not plan to play any of the AD&D Baldur's Gate games because I feel that BioWare is just bad at writing (to many black and white choices and generic plot). Anyway can you tell me the basic like the dreaded THAC0 and dice rolls.

you don't really have the know the rules to play the game, it's all behind the scenes

And besides that, fighting is really trivial in this game because you literally cannot die during normal fights...not in a game over way at least.

This game is more like a western visual novel with combat thrown in as a little distraction.

Personally I don't get along with the Baldurs Gate style D&D gameplay but I love this game for the adventure elements which take on a much bigger part than combat in this game imo.

An explanation of THAC0, dice rolls and other AD&D second edition stuff can be found here if you are interested: http://www.gamefaqs.com/pc/564658-the-dark-queen-of-krynn/faqs/8566

But you don't need to know that much for playing the game.

The lower your thac0 is, the better your chance to hit, the lower your AC is, the better your chance to avoid getting hit, if you know this you already know more than you need.

Many players have finished AD&D 2E games without understanding the rules, the computer knows them and makes the calculations for you.

So, who do you like for CRPG writing. Obsidian, I assume, based on the above, and I agree but I find Bioware at least Obsidian's equal up to DA2. If it's based on NWN 1, that was a notable exception, though the two expansions were much better.

BG series, Jade Empire, Knights of the old Republic, DA0, ME1 are all exceptional, IMO.