It is useful to mention your budget and what the main use of your PC will be,I am assuming gaming as you have chosen a GTX 670 graphics card.Is this a system you are building yourself?
Case: Is this it XION. I have never heard of this brand and I have been building for a while.To be honest you can do a lot better for that sort of cash.Are you in the states as I can only find the case there?
You do not mention one of the most important components which is the power supply (PSU) this should be not less than 650W and a decent brand as a cheap generic brand of PSU can cause a lot of damage should it fail.
Other components are obviously hard-drives and I suggest a 128GB SSD for a boot drive and programs with a couple of 1TB HDD for storage.
For OS then Windows 7 is the better choice in my opinion.