I wish to download Linux and eradicate windows from my gateway pc. I want to get it from Dream Linux

http://www.dreamlinux.com.br/english/index.html

It has a multimedia function. Can you tell me do I have to buy the CD's if i live in the USA, or can i download from site. I need this program or a distro exactly like it. Please help.
William Ratliff
talitim@yahoo.com