Unfortunately, unless you buy an antec or cooler master case, the power supply is likely to be crap.
Here is a very nice case for the money:
COOLER MASTER Elite 430 for $40 after rebate I have built out two of them, adn woudl do it again, especially at that price.
You do not need a lot of power for that system, even if yuo unlock the 4th core:
Antec Basiq BP350 350W for $20 after rebate
If you can handle the cash flow, this is the way to go. Also, most likely no taxes, and shipping in a few days.
OK, OK impatient one, go to the store and buy one today if you must!
Coolermaster with PSU for $70 Not sure which store you are closest to. This is available at the central Milwaukee location.
Building with an off-brand cheap case will cut your fingers and frustrate you! Building with an off-brand cheap PSU runs the risk of blowing up your components.
Just saying this so you might not repeat (some of) my mistakes.
I think most of the other stuff will be compatible, but those fancy computer sellers sure make it hard to upgrade.
Do you know if your harddrive sata or ide? Does it have the wide ribbon cable, or the skinny one?