Build a simple debate Website

Build a website aimed purely for people to leave comments on the daily topic of debate set by me. This topic will be known as 'THE TOPIC' and will be clearly published at the top of the main page for users to see. Users should need to register a username an password before they can comment on 'THE TOPIC' (preferably registering via e-mail) Every month there will be a £50 cash reward for the best comment, view or response to a comment/view. This prize should be on the main page at all times for users to see. Each comment left by a user should need my approval before publishing on the page. Once published, users can rate other published comments by clicking 'thumbs up' or 'thumbs down' icon on the comment bubble. (I have given an example in an attached image) In addition, the previous daily topics and highest rated posts can be viewed in an archive. I will rate user comments before publishing. The rating I give should not be seen by users. However, the users with the 'Top 10' ratings by me, should be published on the side of the main page in a 'Top 10' league style format.