Install MSWindz 7 as Virtual Machine on Debian 8

[D&P Dimov]

I need to install MS Windows 7 as a Virtual Machine on a computer that is 
running Debian 8. To do that, I'd like to use software that is not proprietory 
(I know, I know - this may sounds a bit ridiculous...). This Debian page: 
https://wiki.debian.org/SystemVirtualization recommends Qemu, KVM, VirtualBox, 
and Zen. Does anyone have recommendations for which one is easiest to install 
for a novice? I tried the first one, Qemu, but didn't really find a good guide 
how to install MS Win 7 with it.Thanks!