[Build Help] Gaming and Vid-editing PC

I've read the basics but I still don't know much about computer hardware so please excuse my stupidity. This is what I'm planning to use it for:

-I plan to play BF3 and minecraft.

-I've figured out the basics of final cut but, I'm probably going to switch over to the adobe suite.

-I want to spend not much more than $1000.

-I have 2 planar PX171m monitors, a keyboard and a mouse. I'm currently using a 2006 mac book pro.

-I plan on using a monitor to also play xbox 360 and record gameplay.

-A sd card port would be preferable

-A firewire port required

-I live in the US