Hello,
Welcome to forum!
You can check your hardware against FreeBSD HAL. Most NVIDA cards are supported and SATA out of box. In some case you need to download latest kernel and recompile kernel.
http://www.freebsd.org/releases/6.2R/hardware-i386.html
You can download FreeBSD from any one of the mirror site:
ftp://ftp.freebsd.org/pub/FreeBSD/re...SO-IMAGES/6.2/
Are you new to UNIX? If so I recommend getting Ubuntu Linux which is much better if you would like to run Desktop system.
http://www.ubuntu.com/products/GetUb...currentrelease
Let me know if you need any further help !