$800 AUD Gaming Build (Need parts from Specific Sites)

[aliasneo]

Hello everyone, I would like to get myself a gaming rig and was wondering what the best option for this would be.
$800 limit and externals are not needed (Monitor, Mouse etc)
I will be using this for heavy gaming and would like to maximize performance, the games will be played on a 24" screen and I dont know much about computers (just enough to put them together)

Games i will be playing on them:
World of Warcraft
Battlefield 3
Crysis 2 (if poss yet not expected)
and Black Ops / MW3

I mainly will be playing WoW Though and would like to know what kind of average FPS at what settings would be estimated with this build.

I was looking at:
GFX ASUS Geforce GTX 550 Ti 1g 159
CoolerMaster HAF 922 Case 125
AMD Phenom II X4 955 Black Edition 119
ASUS P8Z68-V Motherboard B3 205
Corsair CMP4GX3M2B1600C8 4GB (2x2GB) DDR3 75
Western Digital Caviar Blue 500GB WD5000AAKX 39 (posibbly x2)
CoolerMaster Silent Pro M700 700W 135

the numbers at the end represent the prices btw.
I need to be buying the gear from somewhere in Australia and my preffered sites are
MSI and pccasegear.com as they are both easy and close to where i live

thankyou everyone =D

 

[aliasneo]

PS: I didnt think to mention, but TES: Skyrim will be my main priority to play when it comes out so if poss a gfx card to run it