I have no Internet access, is this because my default gateway is 0.0.0.0?

Yes. The default gateway, usually your router's local network IP address, is your PC's door to the Internet. If the gateway is incorrect, as in this case with the IP address of 0.0.0.0, you cannot "get online".

This is usually cause by Apple's Bonjour service. Use the Microsoft Support KB-970313 article to remove the entry and get online again. To keep this from coming back (it may return with every restart), uninstall the Bonjour service. If you need assistance with this, contact Apple Support.