Yes, it's enough. Though I'm sure you know the i7-4770k is overkill unless you're rendering stuff.
Also, Windows 7 will run any components that Windows 8 will.
Thank you for the answers. How about the second question? Are those components compatible to build together in one PC?
Yes I am aware that it is overkill, but I don't want to settle for the non-HT i5 4670k as I really do want HT.