After you've installed Wireshark on your computer, the only thing to do will be to start the analyzer from the desktop, program files, or the quick start bar.
To keep consistency, this book is written for Wireshark version 2.0.2 from February 2016. In general (but not always), if you look at the version number X Y Z, when the X changes it will be a major release (like version 2), that changes every several years and occur the software completely. When the Y changes, it will usually be additional features or significant changes in some features, and if the Z changes, it will usually be bug fixes and new protocol dissectors. Since new minor releases are released usually every few weeks, you can have a quick look at their release ...