Thanks for the class, its pretty useful if you need to know quickly how many tables are within a database and also create a zip in which you could probably send the data to a trusted source via email.
I did just want to add a note that the tmp folder that is included within the script within the toZip function ($filename = 'tmp/BeanAPP' . '.zip';) is not included so this may fail first time if the users are not aware of it.
Also I am just a beginner so I am probably missing something important here but can I ask why you unset the variables $fields and $properties?
When those variables have been unset the script cannot identify $fields and fields from the tables do not get added to the fields variable for the text file.
Also just as an aside, for some reason using mysql_connect is discouraged as mysqli offers more functionality and PDO is another alternative. Using mysql_connect should work, but in my PHP version (5.3.2) it does not.