FYI, I like to create a custom check command for checking services on windows with this:
command_line $USER1$/check_nt -H $HOSTADDRESS$ -p 1248 -v SERVICESTATE -
d SHOWALL -l $ARG1$
Just feed it in your service(s) as ARG1$ like this:
luca had a good tip about using "net start ....".
What is the error you get when you try to monitor the service?