How do I upgrade from Microsoft Office 2003 to Microsoft 2007?

I have a basic version of Office 2003 with Outlook, Word and Excel. I would like to upgrade to 2007. What is the cheapest way of doing this LEGALLY? I would like to install it on my laptop and desktop. I may need a more comprehensive verion than the basic edition. We run a very small business with 3 employees (including me and my wife) and I am looking for ways of improving our efficiency and organisation so any advice would be welcome.

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).