@ozzyrs,
your Task Manager show Disk Defragmenter as the top process using your resources.
try restarting the PC into Safe Mode and checking the speed from there.
this will only bring up the core, essential processes needed to run Windows, there'll be no AV software or background defrag task or anything else that could slow it down from a software point of view.
if the speed is 'normal' under Safe Mode, than you have something running that needs to be investigated.
get CCleaner from Piriform (
https://www.piriform.com/ccleaner/builds) and go to Tools > Startup and see what is started every time the PC starts.
then go to the Scheduled Tasks tab on that same window and see what can be turned off there.