Intel with Radeon is fine. There's no difference, and no major worries about chipset compatibility. Just make sure that, if you want to CrossFire (which would be unnecessary), buy a motherboard that supports it, and allows for x8 bandwidth through the second PCI-E2/3.0 port when the first is connected, or something like that.
EDIT: You're going with the P8H67 board, which just so happens to be the one I own. As far as I'm concerned, you're not going to get a pleasant CrossFire experience from it; look at the bandwidths in the spec box at the bottom.
G-Skill is, by my reckoning, an average brand to begin with, and the timings for that thing are average as well. Again, if you're not going to overclock or torture that RAM in some fashion, you don't need "eXXtreem heat spreaders". From that same website you linked,
these might be a better choice.
You don't need an aftermarket cooler if you don't plan on OCing. Get rid of it and save money.
The case is fine, and spacious. With your needs, you don't need to worry about a mess of fans or overly much about airflow. Again, those are concerns that are not incredibly important for what you have.
Now, what I'd suggest you do is buy a better PSU with a higher watt rating. CoolerMaster isn't exactly a great brand as far as I know, and wattages deteriorate over time - if you want upgrade possibilities too, get a higher wattage PSU of somewhere in the 600-700 range. That will leave you with some headroom as well, just in case.