Thank you all for responding.
I raised this issue because of the many previous threads related to FTM out-of-memory issues. I thought this potential competition for resources from another program might be another way to address part of the FTM issues.
Anyway, yes - to those who suggested Task Manager - I have used it but to no avail ... so far.
I too thought Norton might check in unannounced in the background, but neither Norton's UI nor Task Manager show this when I get the characteristic slow down and whirring.
As for the autobackup of other programs, this too does not show in Task Manager.
I checked out Malwarebytes - I found it duplicative of the Norton version I have - but Glary Utilities was indeed helpful. My registry etc. should be smoother functioning now. Thank you for that tip!
Maybe I just need to do what I have been avoiding ... a disk backup, scrub my hardrive and re-install everything. Given the many MS update patches I have had over the past couple years, I am sure my system is a cluttered mess.
Cheers and thank you all,