Changes to Category and Tag pages

Hello, These questions relate to the pages that are shown when a user clicks on 'categories' (e.g. http://theholyfish.com/category/travel/) or 'tags' (e.g. http://theholyfish.com/tag/travel-advice/). How do I: 1) Remove 'author' and 'date', shown just below the heading. 2) Make changes to the heading. 3) Change the order that articles are displayed i.e. so they are not in descending date order. Thanks, Mat.