Where are you?
How will you be using this machine?
In a general way, you would be better off lowering the processor to perhaps an E5300 and upgrading the motherboard to a G43/P43
A similar priced option would be an AMD 7750 and 780G motherboard.
Generally speaking, Western Digital is the best HD brand currently, followed by Seagate, but I have no objection to another brand if the price is right for you.