Look at the migration documents. You bring the entire database, the moodle config file and any plugins and the moodle datafolder.
It is normally recommended to migrate first but I normally do what you do, set up the new server, bring down the new moodle code, import my config.php file and plugin folders, copy over the moodledata folder, import the ENTIRE database and then update the config file with new url if there is one and run replace.php on the database.