Essentially its like this:

Your HDD data is gone. Without a backup, you have no way to recover that data except for some advanced (and expensive) data recovery services.
Making the assumption that you are NOT using an unauthorized HDD system to play pirated games, you will have to restore the games from your original discs. Save games are unrecoverable.

Unfortunately, you are not free to discuss the technical information as to how to do this, because the method is commonly used to play pirated content.

*Thread Closed*