I didn't realize it had been so long since I'd played Civilization until I came back here and found my last post made in 2001. I hadn't played a Civilization game since Civ III. 
I just purchased Civ V from Steam and am enjoying every second of it but I have a couple of quick questions. The game I purchased was the 'Gold' edition and includes the Gods and Kings expansion pack.
When I launched the software from Steam for the first time it automatically launched me into Gods & Kings. I'm assuming that from now on all of the games I play will include the expansion pack items? What if I wanted to just play the 'base' Civ V without the expansion pack to see what that's like?
Is it worth it to purchase the additional Brave New World, or is the Gold enough?

I just purchased Civ V from Steam and am enjoying every second of it but I have a couple of quick questions. The game I purchased was the 'Gold' edition and includes the Gods and Kings expansion pack.
When I launched the software from Steam for the first time it automatically launched me into Gods & Kings. I'm assuming that from now on all of the games I play will include the expansion pack items? What if I wanted to just play the 'base' Civ V without the expansion pack to see what that's like?
Is it worth it to purchase the additional Brave New World, or is the Gold enough?