This setup "in theory" would be decent for gaming, but if you want to do some serious overclocking to improve performance, then the core i5 2500 won't do. Yes, it does have Turbo, but thats only when its utilizing one single core. Also, your mobo has an H67 chipset, which will only overclock 4 bins. I would suggest shelling out an extra $11 for a core i5 2500k and a extra $15 bucks for a Z68 chipset, which has unlimited OC (or until the CPU reaches its limit). A board I specifically had in mind is the GIGABYTE GA-Z68MA-D2H-B3 Micro ATX Intel Motherboard. http://www.newegg.com/Product/Product.aspx?Item=N82E168... .
For the extra $15 dollars, you'll get:
* 2 more ram slots
* 16gb more of ram
*2 more pcie 2.0 slots at 8x and 4x, which will come in handy if you want to do SLI
great mobo find. personally i'm a little iffy on asrock, but that's just a personal bias.
I would seriously prefer that 100x over an mATX board for any desktop build - the Gigabyte you chose is good for sure, but I always plan builds around what I think future expansion needs will bring, and mATX never fits that criteria - limited number of SATA ports, RAM slots, and PCI setups will not allow to accommodate for future graphics card needs or anything that requires an additional expansion slot.