1) You're getting the Win7 upgrade. Unless you already have a retail version of XP or Vista that isn't currently being used, or an OEM license tied to that motherboard, then you're better off just buying a new OEM version.
2) Nothing wrong with a 750w, but why not spend a few $ more for a more efficient one? PC Power and Cooling 750w
80+ Silver $89.99 w/MiR. Also a single 12v rail, but that may just be personal preference.
3) The stock 2500k HS/F can take OC-ing to 3.7-4.0GHz, the H50 is unnecessary unless you plan on going much higher, though I'm not sure how much higher you can go with that particular cooler.
4) G.Skill Ripjaws X
$10 more, just saying.
Please read through the thread thoroughly before responding.
Nobody wants to read a wall of text, formatting is your friend.
i5 3570k | 8GB G.Skill 1600MHz | R9 290 | SeaSonic 750X