The forum we're using on our site is a minimalist one designed to simplify the process of commentary. There's no sign-in process. Just write your comment, choose a name & password, & submit. You won't have to check your e-mail account or pass a CAPTCHA test. Once you've commented under a name no-one else can use your chosen name without knowing the password.
If you would like to follow a thread's debate then click the RSS button. Many browsers, including Firefox, will present you with an option to subscribe to said feed. Alternately there exist a plethora of 'News Reader' programs available for Linux, Windows & Macs.