Attempting to build a computer (first time)

Hey there.
I'm pretty much a complete novice at building a computer, but I'm sick and tired of not being able to game for two and a half years so I decided to build one and work to get the money for it. Since I'm new to this I got someone to help me that had built a lot of computers before and seemed to know what they were talking about... hopefully. lol

This is the build we came up with for me. I'm basically just wanting to find out if it's really good, especially since I was reading a review and it looked like my video card sucks.. lol

And since you need to know what I'm wanting to do with my system to be able to judge it, I'm going to tell you. =)
I want to be able to run games out now on medium settings at very least. I want them to run at high with no problem. I'd also like my system to last a while as far as being able to run games well. The games I'll primarily be playing are WoW (or some other MMORPG), CS:S, CoD4, HL2 (and Gary's Mod), Warcraft III TFT, and I'll probably find some other games to kill time with.

And now the list of parts. =)
Case: XCLIO Windtunnel
http://www.newegg.com/Product/Prod [...] 6811103011
RAM:
http://www.newegg.com/Product/Prod [...] 6820231122
Motherboard: Abit Pro IP35 LGA 775
http://www.newegg.com/Product/Prod [...] 6813127030
Hard Drive: Western Digital Caviar SE16
http://www.newegg.com/Product/Prod [...] KS%2b640GB
Sound Card: X-Fi XtremeGamer Fatal1ty or AuzenTech Auzen X-Fi Prelude or Xonar D2X
http://www.newegg.com/Product/Prod [...] 6829102005

http://www.newegg.com/Product/Prod [...] 6829132005

http://www.newegg.com/Product/Prod [...] %2bprelude
Video Card: GeForce 8800GTS or 9800GTX
http://www.newegg.com/Product/Prod [...] 6814130337

http://www.newegg.com/Product/Prod [...] 6814130339
Processor: There's 2 here because I don't know if AMD is better than Intel or not... E6750 Conroe and Athlon 64 X2 6400+ Windsor
http://www.newegg.com/Product/Prod [...] 6819115029

http://www.newegg.com/Product/Prod [...] 6819103228
Power Supply: SeaSonic M12 SS-600HM ATX12V / EPS12V 600W
http://www.newegg.com/Product/Prod [...] 6817151030
CD Drive:
http://www.newegg.com/Product/Prod [...] 6827106073

This stuff is for later... Not necessarily getting it right off.
Monitor:
http://www.newegg.com/Product/Prod [...] 6824001262
Keyboard:
http://www.newegg.com/Product/Prod [...] 6823126009
Mouse:
http://www.newegg.com/Product/Prod [...] 6826105016

http://www.newegg.com/Product/Prod [...] 6826104178


On the ones with multiple choices, I'm really not sure what to go with, so help there would be amazing.

But also let me know what you think about the other parts too. Don't just stick to what I have already... Suggestions are great too. =) I'm buying this with my money, so there's not a rigid price limit, but I'd like to keep it under 2,000USD.

I'd go with the Intel E8400, same price range as the E6750

http://www23.tomshardware.com/cpu_ [...] &chart=435

Is it really worth the 20 extra dollars for .4 GHz?

If I do choose to get an E8400... Which mobo do you suggest?

If youe looking for P35 Chipset:

GA-P35-DS3L is good Ultra Durable All-Solid Capacitor Design Mobo for $89 (no 1394)
http://www.newegg.com/Product/Prod [...] 6813128059

ASUS P5K-E
http://www.newegg.com/Product/Prod [...] 6813131196