A Sony 64GB USB Drive turned out to be a fake USB Drive having only 249 MB of usable space.

Kaspersky Rescue Disk Updater is a Windows Command Script or a batch file which uses KLUpdater to update the virus definitions of the Kaspersky Rescue Disk ISO.

When you boot an unattended Windows DVD(which contains autounattend.xml), you are directly taken to the installation routine.There is no option to launch the recovery environment.However I found a way of accessing Windows Recovery Environment.

You can create a movie DVD containing a tiny bootable Linux Operating System-GeeXbox.This can play your movies,music on any computer irrespective of whether the computer has an installed operating system or not.
You just have to boot from the DVD media.

The GUI of VirtualBox does not have an option to boot a USB drive (Physical Drive) in a virtual machine.
However you can attach a physical drive to a virtual machine using a command line tool that is bundled with Virtual Box.You can then boot your virtual machine from the attached Physical drive.