It goes to show, you can never trust a hard drive. I know its a bit mean to say this, but everyone who has had an issue with there hard drive, has made sure they backed it up next time
You'll just have to be more careful with where you place important data.
As for protecting your files, you'll have an issue getting these back in Slave form since it'd be a different account,
and is best to just place protected files in password protected Zip files instead, so at least you know you can recover them, whatever happens
If the data is really important you may be able to retrieve it using GetDataBack from runtime.org. Slave it to another machine or another master in the same machine and try it.