How to change 'from' name?

How to change 'from' name?

Hi everyone,
I'm trying to have my emails reading as 'Gerry' (my first name) 'from my company.com'. I've changed my name details in the User Details/Mail Account page, but emails are still being received as my First & Second Name.
It only seems to work if I delete all of the users email addresses and sign up again using First name & then 'from my_company.com' for the second name. However, as I am the administrator, I can't delete my own user account.
If anyone can solve this I'd be very grateful.
Thanks,
Gerry.