If you want to add or remove start up application from Ubuntu/Linux mint. Following link is useful for you.
http://askubuntu.com/questions/69810/how-do-i-add-remove-the-hidden-startup-applications-in-ubuntu-11-10-or-later
http://askubuntu.com/questions/69810/how-do-i-add-remove-the-hidden-startup-applications-in-ubuntu-11-10-or-later
