Okay, I'll just go ahead and be stupid. I want to disable Image Checksum in Brasero, and I have found a few instructions like this:

<http://ubuntugenius.wordpress.com/2010/11/15/disable-annoying-creating-image-checksum-in-brasero-after-ubuntu-10-10-upgrade/>

which tell me to go to Applications > Brasero (etc.). 

I... don't know how to go to Applications. So far, everything I've done in Ubuntu either works via the terminal or via the Ubuntu main menu (the power on/off button on the top right of the screen which gives me access to Startup Applications but not much else). How do I access this Applications menu as referenced in the above?