I'm not too advanced with computers, but I can help you out with some questions.
I will let you know that your budget will get you a monster of a computer.
Q1: There is no doubt that the intel i5 4690k beats the amd cpu at gaming.(that cpu is the best for just gaming)
Q2:For the money, the gtx 970 is the best price to performance card on the market right now.
Q3:For the parts in your pc I would pick a z97 mobo for great overclocking on your cpu and maybe sli in the future
Q4: A 1 tb hdd is definently enough for what you want. Besides if you ever need more space you can buy another hdd in the future.
Q5: I'm not too sure on the psu. I would recommend a good 550-650 watt psu. But not too sure on that.
Q6: For your build, I don't think you will be spending 2000 dollars. I'm guessing you will spend probably around $1400 or a little bit less.
I want to let you know that the gtx 970 is a beast card that will handle any game on the market right now at 1080p. But of you want a little more power get a gtx 980, but I don't think it will be necessary. @djexquisite92