Just run the installer and fire up DC++, then enter the settings to set it up according to your preferences (most important is nick, connection mode, download location and shared folders).
You can also download the .zip file (Binary) and unpack it to any folder you like.
By default DC++ will store its settings and create the downloads folder in the directory where it has been installed. You can configure DC++ to use another folder for settings by editing a file called dcppboot.xml located in the install folder. You can specify a path relative to the DC++ executable there.
Use the uninstaller that followed when you used the installer.
If you didn't use the installer: You can delete your DC++ folder, but be aware that dchub://, adc:// and magnet: links will remain in the registry and will point to the nonexistent application. If you disable Register with Windows to Handle dchub:// and adc:// URL Links and Register with Windows to Handle magnet: URI Links options before uninstalling, these registry settings will be removed.
Just install the new version (or unpack the .zip) in the folder your old version was in. Your old settings, queue, favorites will still be there and will be used by the new version.
BEWARE : There are some cases though when a feature upgrade makes impossible to reuse some some kind of settings or data created by an older version of DC++.