The BFG is slightly ovedrclocked, and is $11 more - it's up to you, there is nothing wrong with BFG but everyone here is very supportive of eVGA - due to being very reliable - they also have a trade in deal, where you can swap on your card and get the cost of a new one for part exchange.
Is that 4gb's of memory? - that is not really required, as the system will not require that amount.
I'm not really a fan of Gigabyte, but there is nothing wrong with it.
The 4400 is alot more expensive. But get this instead of 2gb's too much of ram.
The PSU is fine - OCZ is a excellent manufacturer.
Although Samsung is one of the best manufactureers for LCD monitors, but the monitor does not have DVI.....
If you have money left over get one 7800gtx instead of the 6800gt.
Cisco CCNA, Comptia A+, 1/3 through CCNP