Computer Building Help

ok so iam looking to buy a new computer for gaming. i want a computer that will be able to run games such as WoW on high settings with little or no lag. the only problem is that i dont know much about computers so i was wondering if someone could help me out. i want to build a computer i just need someone to walk me through on buying the best components while staying in my budget range. my budget is about 850 shipped and i plan on buying the parts from newegg so if someone could help me out i would appreshiate it alot. i am not looking to build a pro gaming computer just something for medium gaming.

Thanks,
Chris

Ok, here's what I came up with.


Combo Deal:

http://www.newegg.com/Product/Comb [...] mbo.259927

CPU + Motherboard + RAM:
Intel Core i5 750 Lynnfield 2.66GHz LGA 1156 95W Quad-Core Processor Model BX80605I5750 - Retail +

MSI P55-GD65 LGA 1156 Intel P55 ATX Intel Motherboard - Retail +

G.SKILL Trident 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 2000 (PC3 16000) Desktop Memory Model F3-16000CL9D-4GBTD - Retail

CPU Heatsink:
Scythe SHURIKEN Rev. B Universal CPU cooler: Had trouble finding LGA1156 coolers but here's a good one for the price

http://www.heatsinkfactory.com/scy [...] -1100.html - $29.99 + shipping.

GPU:
BFG GeForce GTX 260 Video Card. 896 MB GDDR3 448-bit memory interface.
http://www.heatsinkfactory.com/scy [...] -1100.html - 164.99 w/ free game

Case + PSU Combo deal:
http://www.newegg.com/Product/Comb [...] mbo.250626

Cooler Master Storm Scout Mid -Tower ATX Case +
Cooler Master Silent Pro 600W 80+ certified ATX PSU - 139.98

I am assuming you will use your existing hard drive, monitor, keyboard, mouse and speakers. Here's a great build for the $850 that you have.