The first thing that you do when you open Pages '09 v4.3 and choose your template — is File menu ▸ Save… and give it any name but Untitled.pages. Make certain that the triangle in that button adjacent to the Filename field in the Save panel is facing up for greater flexibility in saves.
Now, autosave is active, and so is the ability to use the File menu ▸ Revert To ▸ All Versions — that allows you to do content recovery from past edits. This is not the panic button if you have accidentally, or purposely deleted a file though. That is another reason to use Time Machine, and automatically backup to an external drive every hour too.
If you get a spinning beachball on opening a Pages document, quit that document, and then press and hold the shift key while you open that document again. Perform a save.
The Pages '09 User Guide links in the Pages '09 v4.3 Help menu have moved, and this invaluable guide is now located at this Apple location. This Apple landing page will have PDF downloads of:
The Pages '09 Keyboard Shortcuts is here. You may want to export this to PDF from Safari, as there is no telling when Apple may pull this content.