Need help with building a gaming comp

Well i was just looking for some advice on which parts to use. My budget is $500 and dont worry about monitor, operating system, mouse, keyboard. And the $500 is not set in stone just dont go too crazy with the price please, also im probably going to be upgrading it. Its pretty much going to be for playing MMOs like GW2, FF14, and some of the new ones that are going to be using the crysis engine. Please and thank you. =]

here's a link that will give you a decent pc for around that money.:- http://www.hardware-revolution.com/budget-gaming-pc-q4-2010/

think i'd opt for the AMD Athlon II X4 620 2.6GHz AM3 95W Quad-Core cpu tho.

Thank you very much, but could i use this case instead?
(Sorry i saw someone say that different sizes are a problem.)
http://www.newegg.com/Product/Product.aspx…D=1dwz0j1y84w03

yes you could use that case with no problems.