Secure Updater installs updates for any programs that are selected in the Select Programs to Update Securely screen. If you uninstall a program that Secure Updater is set to update, it will reinstall it on the next scan.
To stop Secure Updater from reinstalling a program, right click on Secure Updater icon in the taskbar and left click on Select Programs to Update option. Uncheck the program you wish to remove and it will not be reinstalled automatically.
Note that if you ever do want to reinstall the program you removed you will have to manually re-check the box so Secure Updater will start updating it again.