Using PackageMaker

I'm new to this so any help is appreciated. I was able to follow the guide to create my first InstaDMG and it worked like a charm. So I'm on to the next phase of learning how to use Insta2UpDate to include packages in my images. I'm testing out using Apple's PackageMaker. We got Office 2011 at my job and I can't seem to figure out how to make a package out of this. What I have available is an .ISO. On a Mac, when I open it, it loads the ISO like it would any other DMG. I can see there are files in the ISO file which include the installer files (multiple .mpkg files). But I don't know what to do with any of this. This is the same way our Office 2008 is as well. Like I said, I'm new to packaging software so maybe I'm missing something obvious.