I'm really not sure what you mean by "store it as Package"
- Moodle will backup courses in a .zip format, with a .mbz file suffix.
Site backups are one thing - and you could probably do this just by creating snapshots of your server. If you want to take a copy of a whole site, everything, and restore that (as a new site?) then server snapshots is the way to go.
However, when you talk about backing up courses, then all activities within a course will be backed up within each course - e.g. the Wiki that you refer to.