Did you notice the CPU percentage for most of the processes?  Almost
by definition, eliminating a 0% process cannot improve things very
much.

When the System Idle Process is above 0%, your CPU is not being fully
utilized.  Eliminating any active process will only serve to increase
the idle percentage, not improve the speed of what you are doing.

Do you think the mouse moves by magic?  What about the updates to the
Task Manager display you are looking at?  The fact that a task is at
0% while you are staring at the monitor gives you no clue about how
that task supports whatever real work you are about to do.

In recent years, I have worked with Unix, Windows, and z/OS.  All have
numerous system/overhead processes which appear to do nothing.  Some
company spent a lot of time developing the process and usually for a
reason other than to annoy you.

You may not understand or even agree with the decision to launch a
particular process automatically but you cancel it at your risk.  If
you are lucky, you will need to re-boot immediately.  If you are
unlucky, it will obey Murphy's law and cause a problem at the most
inconvenient time significantly later..

If you know the process is related to an obsolete/deleted app, by all
means kill it.  Furthermore, find out how/why it starts in the first
place and kill that to.  And then find it on disk and delete it.  It
is true that some removal tools don't clean up as much as they should.

You have already acknowledged you have an old slow processor.  It's
even older than mine.  This is your trade off.  Is the performance
improvement inherent in a new system worth the cost AND the hassles
(learning and configuring a new OS, reinstalling or buying updated
apps, finding drivers for old peripherals, transferring data, etc)?

Unless your system was paging excessively (thrashing), the improvement
from added memory is normally not noticeable.

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