You can manage your update settings in the Preferences dialog:

Firefox > Preferences > Advanced > Update

However, for versions before version 4, you might be forced to update through another method.

please note that continuing using outdated versions of firefox affected by known security vulnerabilities will put the integrity of your system and all the personal data on it at risk!

By the way, the current version of Firefox is still Firefox 18, but there have been two security updates (18.0.1 and 18.0.2).

Thanks for your input. I am aware of the risks but I also have been burned by so-called updates that were not ready for release. One of them ate my bookmarks. I eventually was able to restore them, but this took time. In my view, a browser is supposed to invisibly provide a service, not something that takes up time to correct. I've been using FF for years, but am now seriously considering Chrome. I'm just tired of getting an announcement every few days that an update is available.

Many thanks. I'll check it out.