I often need to use command line to manage services for Windows. Knowing the name of the service is important. Some of service names are just not related to the display name. Windows Firewall is such a service.
Windows XP: sharedaccess
Windows Vista / 7: mpssvc
To stop Firewall service on Windows XP, type
sc stop sharedaccess
. Similarly, to start it , type
sc start sharedaccess
. Remember to use an elevated command prompt on Windows Vista and 7.