mammikoura, I wouldn't try that option, as I do believe the hard drive is 100% functioning, yet, the unit it is in is failing.
jeo14888, external hard drives work a bit differently I believe than IDE/SATA hard drives (even though, thats what they are underneath), but just using a USB/Firewire convertor inside.
But to my knowledge, unlike internal hard drives, external drives will stay on, spinning, and not switch off when under no use.
We've had 2 external drive cases go so far, yet, for instance with my 250GB drive I have in my computer at the moment which I simply removed from an external case, it is still functioning.
About the warrenty, I don't think my dad really cares as long as he can back up the data, which concludes me to probably try to open it up anyway. Even if it just becomes a standard drive, 500GB's is alot if it works!
Were thinking of bringing together money and buying a desktop for downstairs, better than his laptop, and for cheaper too, so we can use internal drives.
I don't think I trust laptop/external drives anymore (Yet, I do have an MP3 player external drive that is working to this day from Iaudio, though the drive is a Toshiba, after 3 years of on/off use)