Click on the Apple menu in the top left corner and select About This Mac. This will open a window which will give the version of Mac OS X you are running. From the Apple menu select Software Update... which will check if there are any updates available for the Mac.
Mac OS X Lion is version 10.7
[A version of Mac OS X comes with every Mac. You must pay for any upgrades to a newer version] Not if you use torrents(:
You can install the Mac version of LimeWire on Mac OS X. (See links below)
Yes, it is. Any type of MacBook that comes out now is a Mac OS X. The most recent version of Mac OS X is Mac OS X Lion, coming out soon.
No.
The current version of Apple's operating system is Mac OS X 10.7 (Lion).
Adobe Photoshop version 7 was the first version for Mac OS X and was released in 2002.
As of December 19, 2010 latest version is Mac OS X Snow Leopard 10.6.5, Build 10H574.
Each version of Apple's Mac OS X is named after a big cat. Mac OS X 10.5 is called "Leopard".
I would have to say Mac OS X 10.4 Tiger , Or Leopard
No.
It's possible that the Mac OS X version that is installed on your MacBook does not meet the minimum system requirements for iTunes 9. The minimum compatible version of Mac OS X is 10.4.11. If your MacBook has not been updated to at least that version, just run Software Update ( -> Software Update...) until you're running 10.4.11. To tell what version of Mac OS X you're running, go to  -> About This Mac.