If SBS takes forever to shutdown, add:

                               net stop "microsoft exchange information store" /y                               net stop "microsoft exchange internet mail service" /y                               net stop "microsoft exchange message transfer agent" /y                               net stop "microsoft exchange directory" /y                               net stop "microsoft exchange system attendant" /y                               net stop "modem sharing service" /y                               net stop "microsoft winsock proxy service" /y                               net stop "microsoft proxy server administration" /y                               net stop "microsoft fax service" /y                               net stop "microsoft dhcp server" /y                               net stop "computer browser" /y                               net stop "net logon" /y                               net stop "alerter" /y                               net stop "messenger" /y                               net stop "server" /y
to the batch at tip 166.

You might also want to look at tip 083 and tip 033.