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Your tale of woe is very painful, ArgentGrace. The same thing happened to me once, and I felt exactly as Qwerty07 described. It's not just losing the movies, what about the enormous time spent, researching, locating, filling out the CAPTCHAs, the downloading... horrible.
Since then, I have always invested in duplicate hard drives. A hard drive can go at any time, often without warning.
This is one reason why I usually steer away from the giant-sized files; you not only have to find the space for them on one drive, but two. (Anyone reading this who has not invested in back-up drives - you had better not delay.)
I hope you paid heed to Casshern2's advice, and checked whether the problem is definitely the hard drive; hooking it up to another computer was a great suggestion. Once you know beyond a doubt that the drive has kicked the bucket, there are a few things you can do, short of going to an expensive data recovery service.
When mine went, I did some research, and enlisted the aid of a company in Canada which switched... ohh, I forgot the technical terms now, but each drive has a plate that you can unscrew on the bottom (do not remove the cover! If any dust gets on the inside of a drive, that's it). This plate has the drive's signature, and theoretically, when reproduced, could get the drive going again - assuming the problem is not a mechanical one. The experience cost fifty dollars. Did not work; I had to build up the collection anew.
Other advice includes freezing the drive wrapped in paper towels and placed inside a sealed plastic bag (do a little research for more exact advice), and there have been times when a drive can "wake up" for a short spell, allowing you to quickly make a duplicate copy. (Make sure you have your new drive ready, because the waking up is usually good for only a temporary time.) This did not work with my drive. (And really, you should not ordinarily be subjecting a delicate instrument to such shock treatment, but there comes a point when you have nothing to lose.)
Not long ago, I had another drive go out on me, and I remembered another tip - rapping the drive once, sharply, against a solid area. This didn't work with my drive full of JAV, but it actually worked with the more recent drive. I quickly copied whatever I needed to salvage from it.
EDIT:
In response to the post below, you only bring a drive into a clean room if the drive is to be opened; but opening the drive is not an option for the inexperienced.
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