We have a How To that was made for the contact form that lets you know how to remove the captcha if you do not want it included. Here is a link:
cfsp_removingsecurity.pdf
As for the security question that you see it is chosen at random and is provided by the WA_ValidationToolkit > WAVT_CaptchaSecurityQuestion.php page. You could modify this page if you would like to control what questions are available.