LarvalExtractthat RAM is waaaaay overkill (8GB of 1600Mhz is perfectly sufficient), motherboard could be a little better (try a Z87), i'd go with a 600W power supply (500W will work but for a little extra money it's nice to have the extra headroom), personally i wouldn't buy windows but it's up to you.
other than that though nice build
The site that I'm looking at to build the pc includes a free copy of windows 8.