How can I remove the 'Archives widget' and the 'Meta widget' from the pages on my blog -- for example, on this page: http://richardclunan.com/ ?
And how can I remove those from every page but keep them on the blog ?
I would recommend the plugin Widget Logic. It adds a text field under each widget in the appearance -> widgets menu that lets you add conditional filters. For example if you wanted a widget to only display on your blog page you would add,
Also, check the Conditional Tags to see all possibilities.