The things I've seen in this thread cannot be unseen... and they are atrocious.
My friend, I can PROMISE you a simple and cheap build that will amaze you and your friends - I've made identical builds that play Crysis on High settings at high resolutions and get smooth fluid stable framerates. Overclocking is made easy and does all the work, no experience needed.
Intel E1200 Celeron -
http://www.newegg.com/Product/Product.a ... 6819116064 - 53.99
Gigabyte P35 Motherboard -
http://www.newegg.com/Product/Product.a ... 6813128337 - 84.99
G.Skill 2GB DDR2-800 -
http://www.newegg.com/Product/Product.a ... 6820231121 - 29.99
Rosewill Case 120mm fan -
http://www.newegg.com/Product/Product.a ... 6811147110 - 26.99
Rosewill 530 Watt PSU -
http://www.newegg.com/Product/Product.a ... 6817182160 - 49.99
Hitachi 320GB HD 16MB Cache -
http://www.newegg.com/Product/Product.a ... 6822145129 - 49.99
GeForce 9600 GT Graphics -
http://www.newegg.com/Product/Product.a ... 6814500019 - 94.99
Asus DVD Burner -
http://www.newegg.com/Product/Product.a ... 6827135169 - 19.99
Keyboard -
http://www.newegg.com/Product/Product.a ... 6823233001 - 6.99
Mouse 1600 DPI optical -
http://www.newegg.com/Product/Product.a ... 6826623004 - 11.99
Total: $429.99, allowing space for changes and shipping and handling, etc.
I'll give a quick explanation for each component since they're not picked out of random, or out of any single specific reason:
I've had experience with most of these components, minus the keyboard and mouse. The Intel CPU is a Core2Duo with less cache (but the same as an AMD dual core) and slower clock & bus speed (which can be cured by overclocking - I took it from 1.6 Ghz to 2.66 Ghz on AIR, and its been stable for over a year now). The RAM overclocks to 1,000 Mhz easily, and gives me no problem. The motherboard is needed to achieve this overclocking easily - its VERY rich in features, and allows you to overclock without any trouble - it'll make most of the adjustments for you. Its highly reliable, and just a great all-around motherboard - it will allow you to upgrade in the future. I benchmarked a rig with the same mobo, RAM, and CPU recently - and it crushed a similar AMD X2 5200 hands down. The 5200 was pretty far behind in overall performance.
The case is mainly by preference, but I picked something with space and a 120mm fan in order to keep everything cool and provide great air flow. The power supply is 530 watts - has a PCI-E connector, and good amperage. It has Active PFC and over-voltage protection. All too often people overlook these things, which is a grave mistake - you cannot overheat components my friend. You also can't afford to rely on some no-name power supply giving poor performance to your components, which results in poor performance in general and also possibly damaging them in the long run.
The hard-drive is a good mid-performance drive - 320 GB of space, and 16 megs of cache. You do NOT want to make the mistake of picking a poor performing hard drive - it will bottleneck the rest of your system. This drive should keep up well with your system, and when you're ready to upgrade in the future you can use it as a backup or secondary drive.
The graphics card isn't top-of-the-line, but it is a good graphics card - if you take some of the leftover cash, you could easily upgrade to an Nvidia 8800 GT 512. The 9600 GT is adequate for this system - it can run games like Crysis on medium-high settings and resolutions, but costs less than 100 bucks.
As for operating system, I'd go with Vista Ultimate x64 - thats what I run on all my rigs and it doesn't disappoint. If you're looking to keep budget though, go ahead with Windows XP Home SP3... good enough to do the basics.
Like I said - I have personal experiences with all these parts - and let me tell you. This machine will PERFORM right out of the box. You'll be able to upgrade for a long time to come, and it'll definitely perform. This I can PROMISE. In fact - if you wanted help with the overclocking, or anythin at all, I'd be willing to give it.
In any case, PLEASE don't buy the garbage that has been mentioned previous to this post - especially the AMD build you posted. Not only will those computers have LESS than HALF the power and performance of this computer, you'll be paying the SAME or MORE for worse performance... its not logical or fair IMO. It pains me to see such things haha - I think everyone should get the most bang for their buck.