I don't have firefox and I'm getting firefox updates in the "Software Updater" how can I fix this or disabled this update because I don't want update files on my computer that will do no good.
If you still have firefox installed, and haven't uninstalled it, then you'll still receive updates.
To start, open a terminal with CTRL + ALT + T.
Your prompt should look something like this (names probably won't match:
Then, you should run the commands below in order. When it asks for a password, enter YOUR password. Nothing will appear as you type your password. That is intended and normal behaviour.
sudo apt-get purge firefox
To Update the List of Software Updates:
sudo apt-get update
sudo apt-get dist-upgrade