Suggestions/Finalizing $600 budget Christmas time Gaming PC

How is this looking, Mobo/psu and everything?
CPU Intel Core i3-3220 3.3GHz Dual-Core $119.99
Motherboard ASRock H77M Micro ATX LGA1155 $69.99
Memory Patriot Viper 3 8GB (2 x 4GB) DDR3-1600 $25.99
Storage Western Digital Caviar Blue 500GB 3.5" 7200RPM $59.99
Video Card MSI Radeon HD 7770 GHz Edition 1GB $109.99
Case Cooler Master HAF 912 ATX Mid Tower $49.49
Power Supply Corsair 430W ATX12V $34.99
Operating System Microsoft Windows 7 Home Premium SP1 (64-bit) $91.99
Total:$562.42

I'm playing games like WoW, Dayz, D3. I might maybe stream, maybe. I already have a dvd drive and I was told to get Windows 7 instead of Windows 8 because Windows 8 has some bugs with a few games. By Christmas time should I just get windows 8? Is the PSU sufficient enough and how is my MOBO looking? By the way, any good looking cases that are equalivent/ a little more/ less than the value of the HAF 912 that look good and have great airflow/space?
Resolution: 1365x768 or something like that. Will plan on upgrading monitor/ other parts in future of needed. So I guess the overlying question is: Is this a solid build? As you can see I have a little extra lee-way money wise, so I can buy more expensive parts if needed but would like to keep the price as low as possible. I live in Anchorage Alaska BTW, NO MICROCENTERS AROUND ME.