When I tried to populate data in Zend form "guru", it was returning \"guru\". How can I escape or remove the "" from the text field and populating form data without "" as guru?
Make sure you have Magic Quotes disabled in your php.ini file. They are marked deprecated in PHP 5.3 and are marked for removal in PHP 6 (possibly 5.4).
Use get_magic_quotes_gpc() to find out if it is enabled, and see magic_quotes_gpc option to find out how to disable.
// Are Magic Quotes enabled?
var_dump(get_magic_quotes_gpc());
If this returns true, open your php.ini file and make sure this line = Off
magic_quotes_gpc = Off