This is a direct copy-paste of my review for Baldur's Gate - Enhanced Edition, as it pretty much covers everything I have to say about the sequel as well:
Personal rating: 10/10
Budget: If you already own the original, buy on sale only.
Lenght: ... It took me years to finally complete it. I'd wager an experienced player can get it done in a week or more. No less.
Baldur's Gate is hands-down one of the best games I've ever played. While initially, porting D&D into a tactical real-time gameplay setting should set off some alarm-bells, this game is one of the most tactical games I've ever played, requiring precison, patience and understanding.
It's also a roleplaying game that allows you to explore the, now venerable Forgotten Realms setting that I grew up with (Fantasy books ect.). It features a soundtrack and memorable characters that you will NEVER forget. You'll find yourself hearing things in real life, that almost makes you burst out a quote from this old gem, that no one will get.
The biggest problem with Baldur's Gate, is that it's ancient by now... Which is where the enhanced edition comes in!
Upgrading the game to HD and even upgrading the game engine and interface to the same standard as the sequel is exactly the kind of boost the game needed to become playable, even to people who didn't grow up with it.
Enhanced edition also features some new content. While I appreciated this, I'll be honest and say that I didn't quite feel that this new content entirely fit with the mood of the original game. It was a bit too... Humorous and... Cute. I mean, considering the rather dark underlining theme of the game and the story, it just didn't feel quite right, but this is to be expected as the update was done by a third party.
Baldur's Gate, to me, is the predecessor to all modern RPG's.