looks fine to me,things i would consider changing are
hdd SeagateBarracuda 7200.12 2TB 64MB Cache Hard Drive SATA 6 Gb/s 7200rpm - OEM | ST2000DM001 pretty quick drives for 2tb depends on whether its cheaper or not much more than the wd drive but upto you
memory Newegg.com - SAMSUNG 4GB 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model MV-3V4G3/US
why that memory? read the reviews,dirt cheap and clocks to 2133mhz +,and its low profile which is better imo if you decide to fit a large cpu heatsink
EDIT: ohh and why a z68???????????????? GO FOR Z77!!!!!!!!!!!!!!! motherboard your 2600k will run fine on it,unless you choose ivybridge cpu?