Thanks Bill2 for your suggestions I worked down the list without success until I got to the MS fixit option.
Although I was unable to run the Fixit utility, each time I tried to start it, the system stuttered to a halt and I had to reboot, so I moved down to the BITS and update .dll list and re-registered them (excluding a few that were not recognised). Once I rebooted the indows update list was cleared and when I checked for updates I was presented with the 2 that had failed before. Eureka! They updated ok.