Is my available hardware adequate?

Im spending my time reading sifting through this community to take my shot at an HTPC build.
Based on eskro's sticky I would fall in group six.
My question is if I could come up with something that would work well out of the pile of hardware listed below?
A suggestion as to what to keep and what i may need to add.

Thanks for your time!


INTEL E8500 3.16 revision EO @ 4.25 GIGABYTE GA-EP45-UD3P ASUS tri fan 4870X2 2Gx2 OCZ Reaper HPC
2 Western Digital Caviar 640GB In Raid Lite on Blu-Ray / LG DVD
CORSAIR 750W

and

AMD Athlon 64x2 5000+ 2.6
G.Skill 4GB (2x2GB)
ASUS Xonar Essence STX Logitech Z5500
MSI K9AGM2-FIH
320GB and 640GB WD sata
XFX Alpha Dog 8800GT
Seasonic 500 Watt