Your .org domain is hosted with another hosting company and your .org.uk is hosted with BT so we cant change the root for your .org domain.
I haven't done this myself but I have checked out a few sites and there are various ways to redirect a website a website. You can use html redirect, 301 redirect using htaccess/Mod_Rewrite/CGI/Perl/ASP.Net/Java and the list goes on, the best thing to do would be to ask your current hosting company what methods they support on their FTP server. I don't know if your hosting company gives you any tools/support with the developing side of your website so you should also find out if you have to write the changes into the script yourself. There is basic scripts online for doing this but I would check with your hosting company first.
If your hosting company say you have to write the code yourself then I would do a Google search, I wrote 'how do I redirect my website' and there is some codes and explanations within the first few sites.
