Web 2 is one of those terms that actually means nothing, but is used by many to mean a site/design that includes such things as 'glow' buttons or user interaction with the site, (think facebook).
Web 2.0 is a format of website that allows user interaction, has a more robust, user-centered design & interface, allows for inter-operability and scalability.
Twitter, Facebook, Google are some key examples of Web 2.0 websites. There are more - foodily.com is one of my personal favorites.
Its meaning has evolved and morphed in recent years
1) My doubt is any static website called a web2.0.
2) Any chance static website convert to web2.0. what is the fundamental step.
Trends I'm seeing at present: