CPU: i5 2500k is a great cpu. Best bang for you buck with gaming and every day tasks.
MOBO: Gigabyte is a good brand but there are better boards out there for you price range. I reccomend ASUS, they have a better warrenty then gibaytes 2 year one. Plus they have an easy to use BIOS system for beginners and one of the only boards to have an automatic overlocking feature which is nice if your not 100% on how to do it manually. I recommend you take a look at the p68 boards. Theres one that pretty much matchs every price range. My favorite being: http://www.newegg.com/Product/Product.aspx?Item=N82E168... Its more expensive then yours but, i see your buying at microcenter and i dont know if there still having the buy a CPU get $50 off a mobo offer. If they are is comes out to the same price. If not they have a p68 board for almost any price range. Plus the p68 are fully compatible with the new ivy bridge CPU's coming out later this year.
PSU: OCZ isnt the best brand for PSU. You should look into a Corsair or Seasonic PSU. http://www.newegg.com/Product/Product.aspx?Item=N82E168... 750 watt, for $105, non modular but its a way better PSU then the one you got. Alot of problems with builds stem bad PSU's and RAM. So its worth the money to invest in a good brand.
I think you did a great job overall. I love that case and it's features.
I am a fan of Gigabyte boards. They are every bit as good as Asus.
I do agree with the above poster in that you can do better on the power supply. For a few extra dollars you can stay modular and move to an 80+ Gold rated power supply from one of the best manufacturers in the business.