Your money and your plans, I just think you can do better with just a little more money. You're spending 500 dollars on a C2D machine that will only be marginally faster then what you have now. I don't think it will be substantial but hey like I said its your money.Well, ill actually be going from a dual 2.4ghz to a dual 2.9ghz with 3mb of L2 cache. And 2GB of 667mhz DDR2 ram to 4gb 1333mhz DDR3 ram. And my crappy 256mb GPU to 1GB PCI Expresss.
I will also be able to easily overclock. So id say thats a pretty substantial upgrade and your substantially crazy for thinking otherwise.
Good luck