Yes but it won't read it, only 2GB will show as that is the maximum if i've correctly understood how it was written. Your motherboard only has two memory slots too. Both of those items you selected would work yes, Ram would clock itself down from 800mhz to 533mhz as the latter is the maximum your motherboard can give.
I would rather you save your money for a while longer and buy more recent parts as the 775 socket is rather dated and so is DDR 2.
Even though that processor is a far better improvement over the single core you currently have it will still not suitably play GTA IV.