Case - I would go with a coolermaster
http://www.newegg.com/Product/Produc...82E16811119047 ... they are the most popular cases around, and for a reason. ( it fits everything in my case at just the perfect size , and keeps my rig QUIET )
Video card - Beef it up, that will bottle neck your rig. I recommend a
http://www.newegg.com/Product/Produc...82E16814129113 ... best bang for your buck on the market right now.
RAM - You NEED 4GB+ for multiboxing. The ram you chose is fine, but double that Quantity!
Processor/Mobo - Good choice, I see no problems there
Power Supply - Great power supply, but if I were you... go with the new and exciting Modular cable system. ( I have the exact PSU as the one linked, except Modular )... Modular is designed so you only use the cables you need, it cut my case clutter in 1/2 easily ( and only for a bit more $$ )