What to do when both SFC and DISM scans cannot restore corrupted system files?

In December, a Windows 10 update corrupted some system files on my computer (i7, 3.7 GHz, 16GB, 64-bit, Windows 10 Home, 22H2, build 19045.3693). Since then, I have run, as Administrator. from cold boot, multiple scans with SFC /SCANNOW and all three levels of DISM (CheckHealth, ScanHealth and RestoreHealth). All SFC and DISM scans hang at 47.8%, reporting that they cannot restore some corrupted system files. Several more recent Windows 10 updates have occured, but have not fixed the corrupted system files. Almost all programs are randomly failing to respond to commands, or pause interminably. Task Manager sometimes frees them, and it sometimes allows a Restart. Otherwise, a restart requires powering the system off. I can find where the failures occur in the dism.log, indicating "cyclic redundancy check" (Error 23 or Error 27), but I'm not knowledgeable enough to know what else to do. Since the Windows 10 installation upgrade was made from Windows 7, I also don't know how to download or create a current Windows 10 ISO file, or how then to direct the DISM RestoreHealth "source" scan to whatever folder where a current ISO file might be stored. The computer has been unreliably erratic for over three weeks, and can't be trusted to complete any but the most basic operations. Has anybody else gone through this ordeal and found a way to fix the files, without installing a new installation of the Windows 10 operating system and losing all programs and data? Thank you for any suggestions.