The last version of hiren's is 15.2, as it says on their website, though it's from 2012. Here's a link to the iso:
http://www.hirensbootcd.org/download/
You would open the iso with any cd burning program and burn it. The result should be a cd with a load of files and stuff on it. You would then set your computer's bios to boot off your cd drive and then boot off this disc. A boot menu should appear telling you what you can start up. If you don't spot something in the boot menu, it's inside the windows xp bootup option. It's a great utility, just wish it was updated (since it's 3 years old, it might not recognize everything anymore, especially in its stripped down windows xp environment).
Honestly though, I would just go ahead and backup your stuff right now. Not much point in taking that risk if you have stuff you want to keep. Backup your files and then use hdd tools if you still want to try and use that drive. If you want a full drive image, Paragon Backup and Recovery is pretty decent with its free version
http://www.paragon-software.com/home.../download.html .