I did go into safe mode and tried to reset through CCleaner. Only one driver was listed which was one that I'd done seperately. The restore failed. CCleaner still reports the same seven drivers need updating.
Although I checked prior to running the update it did not create a restore point (nor, foolishly, did I) so my only option is to reset. As this will almost certainly lose a couple of significant programs I'm loathe to do that if there's a way to track down the source of the problem.
Is there any chance that updating the drivers one at a time would work?