If I install Windows 7 on a partition of my hard drive will I keep all the files from my primary OS? -

I have the Windows 7 installation disc ready and I plan to install it on a partition of my HDD, meaning that when I turn on my computer I am given the option whether to boot up windows 7 or my old OS. If I do this, will all my documents, videos, applications, etc from my old OS be moved to the Windows 7 OS while they still remain in my primary OS? if not, will i have to copy them over, therefore doubling my hard disk space?

They will remain. I suggest looking up the proper way to dual boot so you don t have any issues.