You might consider a larger hard drive for the same cost: HITACHI Deskstar 1TB
While the SATA interface is 3.0Gb/s, rather than 6.0Gb/s that your listed drive boasts, you probably won't see any difference in speed due to the hard disk itself being the bottleneck.
What operating system are you planning to use? As far as RAM goes, you really don't need more than 4Gb and you won't be using much more than 3Gb of that if you install a 32 bit operating system. Even with a 64 bit OS, I suggest 4Gb in two dimms. The motherboard that you list has 4 dimm sockets. If you install two dimms, then you could always install two more later if you need more RAM. I suggest G.SKILL Ripjaws Series 4GB (2 x 2GB)
This RAM is slightly faster than what you have listed, although 4Gb rather than 6Gb.
One thing that I don't see listed is a DVD ROM, the ASUS Black 24X DVD+R
is worth considering.
The motherboard and processor look good to me, the video card I'm not familiar with so I won't comment on it. I'm sure you will get others with video display adapter suggestions.
Let us know what OS you are planning to use...