Dungeons and Dragons - Gamersgate or GoG?

Temple of Elemental Evil was fantastic (once patched). I have no idea why they never used that engine for another game. It was exactly what I was looking for in turn-based wonderful.

Note: I realize this doesn't help you choose, I just needed to say it, because I think it's often overlooked, while people talk about Baldur's Gate and Torment all the time.

Don't know what sort of games you like, but I bought each one of those games at retail when they were new, and they were worth every penny. Planescape: Torment is regularly placed near the top of various all-time greatest pc games lists, but they are all good.

And as you suspected, the steam version of Baldur's Gate is not the same, it's the new "Enhanced Edition" - which I have not seen. Gamasutra has a nice writeup here.

The price is awesome and I'm really itching to buy but I just keep hoping this bundle will come to steam sometime soon

Steam's Baldur's Gate is the Enhnced Edition. The others are normal. The Gamersgate versions are the same as the GOG versions these days, so unless you really have a nerd boner for the extras, just get them where they're cheapest.