So I'm on a budget and I'm also a very light gamer. However I do want to build a new computer soley for the purpose of running Modern Ware 3 on med settings without lag. Due to my budget of about ~$300 I am not trying to get a top of line future proof system. Just something to curb my light gaming side and play only Modern Warfare 3.
I looked online and these were the minimum system requirements I had to get
Minimum System Requirements:

Operating System: Windows XP / Windows Vista / Windows 7
Processor: Intel Core™ 2 Duo E6600 or AMD Phenom™ X3 8750 processor or better
Memory: 16 GB free hard drive space / 2GB RAM
Video Card: Shader 3.0 or better 256 MB NVIDIA GeForce™ 8600GT / ATI Radeon™ X1950 or better
Sound Card: DirectX 9.0C or late

With that in mind, I can reuse my old case on my computer, hard drive and DVD drives, and MAYBE even the power supply unit. I'l also be picking up IDE to SATA adapters since my old motherboard was using IDE cables for the drives and im guessing newer motherboards will most likely be on SATA.

So then I started thinking, AMD or Intel?
With the AMD i can get quad core and it can get be better value, but at the same time I know currently Intel is doing very good on their processors, but if I were to go with them it would probably be just a dual core.
So I made a build for both below

AMD Build
CPU
http://www.newegg.com/Product/Product.aspx?item=N82E16819103889

RAM
http://www.newegg.com/Product/Product.aspx?item=N82E16820231426

GPU
http://www.newegg.com/Product/Product.aspx?item=N82E16814121474

Mobo
http://www.newegg.com/Product/Product.aspx?item=N82E16813131657


And then the Intel Build
CPU
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115078

RAM
http://www.newegg.com/Product/Product.aspx?Item=N82E16820148262

GPU
http://www.newegg.com/Product/Product.aspx?Item=N82E16814102940

mobo
http://www.newegg.com/Product/Product.aspx?Item=N82E16813138332

PSU
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371029


So a rough idea if I were to get an intel vs a AMD would be something like the above. However, im not great at picking parts so I'm not sure how those parts are in terms of performance and the technical benchmarks.

So What do you think? Should I get an AMD build or an intel build? And if either or, are my parts okay or do I have to completely re pick my parts? What do you suggest?

Thank you for your time.