What kind of website do i need, and what to ask for?

Okay so im looking to make a website for my business. i want the website to be web 2.0 that way its all search engine optimized. I also want my website to have some sort of database in it so that once my customers input their data i can easily manage it and store it. what kind of website do i need, or what do i ask for to have it done and managed by someone.