Twice now, I have recorded series 8 of 24 on my sky+ box and both times the hard drive has given up before I have got it watched

Why does it do that?

Voodoo

Fat fingers on the buttons???

Could be worse, it could have not recorded in the first place because the drive's full of drivel that your kids have recorded and have no intention of watching

Buy the DVD???

Its done you a favour the acting and story line are that bad even the hard drives rejected it.
Cheers,
Bob