You can copy from one hard drive to another using copy+ but obviously you will lose anything on your box and would have to take them apart / use pc to do this. The files are encrypted so can only be played through a sky box.
There are hd recorders about but these are expensive and I forget the name.... Think it was hauppauge.
... and they'll only play back on the same card (and possibly box)
If he's got a box with component out, as mentioned above, you can get component capture devices for PCs and do it that way, but you lose some quality as it's going over analog and it's a big hassle anyway.
Oh and if he does record it to (say) a DVD recorder over SCART it's SD resolution but it's still a lot better than a normal SD broadcast.