Yes, You have to have SSL Certificate for, Register Page, Login Page, Forgot Password Page and if you have any specific pages where users used to fill confidential details. I feel that having SSL certs for your site will be beneficial, as users will donate online and online transaction will happen, and credit card information and all such sensitive information will require for the same purpose. The more customers trust you, the more they donate. An SSL certificate encrypts the connection between the browser and Web server. And protect all sensitive data from hackers and fraud.