I downloaded TestDisk and ran as specified in the link. Currently my PC has been running testdisk_win.exe for 48 hours exactly and it's only analysed 10%, i.e.:
TestDisk 6.14, Data Recovery Utility, July 2013
Drive H: -2000 GB / 1862 GiB - CHS 3906961408 1 1
Analyse Cylinder 417529856/3906961407: 10%
Read error at 417529855/0/1 (1ba=417529855)
Am I running the wrong thing, i.e., should I be running some RAW--> NTSC retrieval thing rather than this Analyse Cylinder? In that case should I hit "Stop"?
I'm kinda concerned that it's going to take weeks to get to Analyse Cylinder 100%, and then I find that I ran the wrong thing

Thanks, mate, for your assistance.
Cheers, Sat