Today I came across what I believe to be a shortcoming with MOSS 2007. There doesn't appear to be a way to quickly unpublish a page through the user interface. When you go to the settings for a page, you can choose to unpublish the version of the page, but if there are multiple versions of the page, then you have to go through and manually unpublish each version. Right now this isn't a huge deal since most pages probably only have 1 or a small handful of versions, but as time goes on, unpublishing a page that has been posted and updated numerous times will turn into quite a chore. The other catch is that while you are doing this, old versions of your page will be served up to your site users. Once you unpublish a version, the next one is automatically used for the page.
To unpublish quickly, use the Version History screen for the page and you can go through and unpublish versions from a single location one after another.