I have finally resolved the email issues which have been plaguing the website since I moved it to our dedicated server. This now means that user registration will now be successful, as validation emails are now sent to user email addresses as required. This will also apply to emails sent from the website for lost passwords!
As a side note, I should point out that I have removed all existing accounts, so anyone who had previously tried to register should do so once again. This will ensure you get that confirmation email sent out, and remember to check your junk email just in case!
As these issues are now resolved, I can now resume other work on the website, and in the server. Keep a look out for those changes in the coming weeks!