Thanks bevills1, a good idea. I have a bootable disc and an image of my C drive now. I'm going to test it with another drive installed as C, just to check it works OK. Acronis does do strange things to this rig, just mine, no, there are a few cases of what happened to me on the web.
I don't actually like Acronis much, it was a bit fussy about keeping the settings, like what drive to back up to.
A fresh image every week on separate partitions alternately so the last one doesn't over ride the previous image. Mmm, just in case.