I'm going to create device with Product Id (PID) = 0x0000, create driver for this device and sign it using Microsoft Windows Driver Kit (WDK). Is 0x0000 a valid PID for USB device in Windows?
PID=0x0000 will be a generic PID for all my devices (for development purposes), because I already have PID=0x0001, PID=0x0002 and so on.
Yes. As far as I know, there is nothing in the USB specification that prevents the product ID from being 0, so you should be fine. This listing of USB IDs contains several instances of USB devices with a product ID of 0.
Keep in mind that your product still must have a valid vendor ID, which you are supposed to get assigned to you by the USB Implementers Forum.