Comment 2 for bug 389990

Thank you for reporting this to Ubuntu. Let's address the issues one at a time.
Is the Firefox crash reproducible? What are the steps to generate the crash? You have a large number of addons installed, does firefox crash with them disabled?
Check for update is grayed out because Ubuntu provides Firefox updates through Debian packages and not directly from Mozilla.
There are probably 2 profile folders if you have installed Firefox 3.5 at some point. Firefox 3.5 copies your current profile on install so that you can modify each version independently.

Also, to maintain a respectful atmosphere, please follow the code of conduct - http://www.ubuntu.com/community/conduct/ . Bug reports are handled by humans, the majority of whom are volunteers, so please bear this in mind.