Your OS will be installed.

--Charge it to 100%, whatever amount of time that takes, one hour or six.

--Activate with Cingular. Purchase a BlackBerry Data Plan, along with your voice calling plan. BBDP is must have for data, internet, email, etc.

Sign up your BIS account and add your email:
How to add / delete email addresses - BlackBerryFAQ

You will have service books pushed to your phone for the email addresses and the browser. After that, all should work well.