The answer to this question is very individual. Choosing the right package depends on the type of the website that you will be running.
Lets say you are planning to run a company web page with a few pages about your company, products that you offer and a contact form. Also with a few email accounts for your staff members.
Above is an example of a small business website and you should be fine with any of our small packages. (Mini, Copper).
As you might have understood, it all depends on the amount of webspace and bandwidth (transfer) that you will require.
Also you may upgrade/downgrade your package at anytime so there really isn't an issue if you choose a too large/too small package.
Should you have any concerns, please contact our sales department, we will be more than happy to guide you.