Quote Originally Posted by Cheesemill View Post
I would go for VirtualBox.

However, one thing to think about is if you have a legal way to install Windows as a guest OS or not.
The recovery disks that you receive with a new laptop (or the recovery disks that you create from your first Windows boot) will almost definitely not work for installing Windows as a VM as they are linked to the physical hardware of your laptop, a VM presents different virtual hardware to the OS so the installation will usually not work.

Even if you do download a Windows install CD that works, the serial number that is printed on your Laptop usually isn't legally usable for a VM, you will probably have to purchase a new copy of Windows to get a legal VM installation.
You can remove all occurrences of "usually" from this post and it will be more accurate.