Thank you both for those suggestions.
The disk passes the SMART checks, and I ran chkdsk too which seemed to complete fine. Two passes of memtest didn't find anything wrong with the RAM either. As best I can tell windows repair isn't a feature in Windows 10, I did run a few of the built in repair tools, which didn't find any problems.
The laptop does have the 20GB hibernate drive, which I have already modified the use of sucessfully. I'm not sure if I made it clear in my first post, but the shutdown/suspend features were working without any issue before and then stopped doing so for no clear reason. It also affects Windows, installed Mint 18 and live-cd Ubuntu, all with the same symptoms.
Any further suggestions greatly appreciated.