yes carl a, good advice. and yes, I do not expect help from MS with this. Vista support supposedly ends by April 2017 but I don't feel like switching system now because that machine is also older, RAM and storage limited. Newer system needs more resources.
What I'll do, if/when I ever get WU update fixed, I will make restore point, registry backup and a complete system backup image that I can fall back on when there is trouble.
Otherwise I have no problem with Vista. It has served me well most of the time for years.