Turn off programs

I want to turn off the software updater on this computer. My elderly father is only using it for iPhoto and I don't want him to deal with anything else. I did uncheck the box for updating but it still pops up when you turn the computer on. I also need to get rid of Safari and Mail as he will not be using these. They come on automatically and I can't find out how to turn them off. I removed them from the bar but when it was turned on again, they showed up. Thank you.