I've had Baldur's gate 2 and its expansion for a while now. and decided to play through the game again.
Baldur's gate is nothing short of amazing. It presents an interesting storyline of high adventure, dealing with issues such as nasty dragons, strange murders in a town, a guild war, and even helping out a ‘fish’ king. Combat is fun, challenging and reasonably strategic. you can optionally tune the game to be turn based so you can spend as much time as you need to plan out attacks, reposition your party members, or even just to look at that new item you picked up a monster kill before :D This is all presented in a very detailed pre-rendered 2d world, which even today looks reasonably good. All of this comes together to build a level of immersion that a lot of RPG games since have failed to capture. In Total, both of the Baldur's gate and expansions should provide you with over 300 hours of top quality RPG fun. This is seriously Bioware in their element.
While this game is 10-odd years old, fear not about the game not running on modern hardware/operating systems. Baldur's gate 2 at least runs perfectly on Vista 64bit. There are modes to fix up how the game looks in widescreen mode, a mod to run Baldur's gate 1 on Baldur's gate 2 modified game engine. Ability to push the screen res up, etc.