How to install a version of Windows in Ubuntu 14.04 in a virtual box?

[sasha4]

I am running Ubuntu 14.04, and I want to create a virtual box to run Windows 7 in.
I have followed these steps so far, successfully-
sudo apt-get install aptitude
sudo aptitude update
sudo apt-get update
sudo apt-get install virtualbox
virtualbox

How do I install a version of Windows in this virtual box?

[TheFu]

Perhaps the best thing I can say is to check out youtube for step-by-step installation instructions.

Your Windows license will need to allow virtualized installs, which generally means no OEM disks which are tied to specific hardware and check the BIOS.

The virtualbox.org instructions for creating the first VM are clear too.