I first took a backup of my Windows XP system drive (C: in this case) with Aomei Backupper Standard (the free version) last May 2019. I had never done a restore-from-backup with Aomei before as I do not have a spare hard disk drive. Restoring to my healthy WinXP partition is an option but it seems a bit too risky for me. As a consequence, this thought had been bugging me since: Will my restore from Aomei backup work?
Fast forward to 2nd March 2020. My Windows XP kept rebooting that fine morning. The login screen never appeared. I tried mounting the C: drive from Ubuntu. It failed with an error - the NTFS file system on my C: drive was totally screwed. Only one thing to do now - a full system restore from my Aomei backup.