[dba-SQLServer] Remnants or not remnants? That is the question

[Arthur Fuller]

To begin with, I seem to have created a problem with my installation of SQL
2014. SSMS loads fine, but then when I select the default database engine
it reports an error that it cannot find the file. So I decided to
un-install it, and in the Windows Uninstall dialog I see a whole bunch of
references to SQL 2008 etc. components. I'm guessing that these are present
due to installations of various tools such as those offered by Red Gate and
other third-party vendors, but I'm not sure about that. Is my surmise
correct?

So I have several questions.

1. Can I safely remove all that stuff?
2. Suppose I want to remove all traces of SQL Server from my machine, and
start over. How would you suggest I go about that?
3. (I know I've asked this one before, but have forgotten the answer) How
does one restore WIndows 10 to its original setup state? I have all the
install programs for all the software I've installed, but would like to
start completely afresh, then install a couple of truly essential programs,
then create a Restore Point and a backup of that on external disc just in
case. It will take a weekend to start from a virgin installation and then
install various layers of "essential" stuff, creating a Restore Point after
each layer has been installed. I should point out that I have ToDoBackup
configured such that it constantly backs up changes to My Documents etc. to
external disk, so that I'm free to wipe the hard disk at any time without
losing any data; on the other hand, a month ago or so, my external hard
disk died -- but fortunately I have two.

And a couple of comments:

Two years or so ago I bought an external hard disk (SeaGate 2TB) which I
used as a backup disk. It eventually died, but fortunately by that time I
had bought another one, this time 3TB, and everything of importance was
saved also there. But I learned a lesson: one external drive is
insufficient if you really want to CYA.

It has also occurred to me to set up several Win10 VMs, each containing an
instance of SQL Server, Office and a few other essentials, then clone them
all so I can replace any and all at will. Since development is my game, not
so much actual running of the databases, this might work best. It might
also allow me to set up a VM for PostGreSQL, MariaDB, etc., without having
to worry about port conflicts etc. In that scenario, no DB would be running
on my base OS -- ultimately its only purpose would be to host VMs, internet
connections, USB connections, etc.

So that's my plan, in general: create a virgin Win10 installation, back it
up; then install critical software piece by piece (primarily EaseUS Backup
and Oracle VirtualBox and a couple of other critical tools, then backing up
that image, and from then on working within VMs and touching the base
system only when Win10 changes. But if that's the scenario, maybe I'm
better off installing Linux as the base OS. and then the various Windows
versions I need as VMs I have only one hesitatancy here: reconfiguring the
box like this might lose my license to Win8.1 upgraded to Win10.

Not sure how to proceed. If you have any suggestions, I'm all ears.

-- 
Arthur