2015 HP Laptop - Hard Drive Pegged To 100% during First 10min from Startup

2015 HP Laptop - Hard Drive Pegged To 100% during First 10min from Startup

Background:

In 2016-17 I took advantage of MS' free OS upgrade to Windows Ten, Home 
Basic. Original OS on this machine was Windows 8, which interface-wise
 was a hot MESS compared to Vista, 7, and 10 afterwards.

Since then, startups on this laptop have been an eternity.

I did attempt to reduce the pegged HDD(pegged by things like Norton 360, 
and Windows internal startup things like Service Hosts, etc) by setting page 
files to a fraction of factory/recommended settings, and then restarting.

For a few sessions, startup was much faster, but now had returned to a 10-
20 minute ordeal waiting for my pegged hard disk drive to calm down.

I also ran Auslogics defrag, and Malware Bytes, both clean slates.

Any other suggestions on what to check?