you have to “disable” the directory
/wp-content/plugins/wp-recaptcha-integration/
by just renaming it. Maybe with an underscore at first:
…/_wp-recaptcha-integration/
then login in, change manually in the adress bar to …/wp-admin/
then enable in FTP the directory again by re-renaming it, go to Preferences/reCaptcha and change the settings.