No. It is considered USB mass storage once connected to USB port. So you cannot boot from it as an INTERNAL system OS drive. However just like any flash drive, you can boot from it during system startup. Only programs stored on a zip file format can be ran from a flash drive like device.
This is completely and totally wrong. Any harddrive attached via USB is seen as a harddrive. you can install windows to it, you can set it as the primary boot device. you can install programs to it. a zip file is just an achive and CANNOT be run.