As root user ( su - ) run the command: chkconfig --list
That will show the services and if they are set to start in the different runlevels.
chkconfig --list cups
cups 0:off 1:off 2:on 3:on 4:on 5:on 6:off
If you don't want a service to start, change it like this example:
chkconfig --level 2345 cups off