1. Would go for the the 212 EVO, though it is largely a difference in Idle temps.
Though if you are overclocking to 4.5ghz (which will require added voltage), I would be looking a bit higher end toward something like a Noctua NH-D14 or Corsair H100.
2. 850W is more than enough, 750W is the recommended wattage for dual cards, so your set. The mobo supports dual Crossfire/SLI so thats fine as well.
3. No bottlenecks.
If your getting an SSD, I advise a Samsung 830 over the Crucial M4 or any Intel drives.
Also if the rig if for gaming, there is no need for an i7 or 16GB of RAM. Can downgrade to a 3570k and 8GB.
1. That cooler will be fine and i dont know how it compares to the evo.
2. the power supply is more than enough to power both graphics cards
3. you shouln't experience any bottlenecking as all compoenents are of a good quality
1) IB CPUs tend to heat up a lot when you raise the voltage when you OC, usually around the 4.2-4.3ghz mark. you'll need a crazy amount of luck to get a chip that can be OCed up to 4.5 sans raising the voltage. otherwise, neither a hyper 212 plus or evo or an NH-D14 is going to help. a custom water loop's about the only solution i see.
2)i've read people going for 750w for a 2x7970 CF and did fine with it. i reckon 850w is plenty enough.
3)nope. heck, if this is for gaming at most, feel free to go with a 3570k. no benefit going with an i7 anyway.