virtualbox.org

Hello;
I have Windows Vista running as a guest on a Macbook Pro and I would like to update to Windows 7. Can this be done with a digital download of Windows 7 or do I have to purchase the Windows 7 DVD? The reason for asking is that the Windows 7 digital download is significantly cheaper than the Windows 7 DVD, thanks
Sheldon

All of that would be between you and Microsoft. Once you get the installer disc or ISO, Virtualbox will install it.

Note that if the "digital download" is not a legitimate copy bought from a seller with an authentic and activatable Microsoft code we won't be able to help you to fix issues. Caveat Emptor.