Two copies of Windows and other apps on 2 physical drives

My desktop PC has 2 physical drives, C and D (which is from a previous PC).

Both drives have Windows folders with hundreds/thousands of files in them......looking like complete copies of Windows.

Couple of questions:

1. Which "one" of my Windows is actually booting up when I start my computer?

2. How do I get rid of the "other" Windows?

3. Both drives also have copies of Malwarebytes......Paintshop Pro, Revo Uninstaller, QuarkXPress, etc. How do I know which one......from which drive......is the one that launches when I click it on the Start menu?

Stupid sounding, I know, but BAFFLING.

This all started when I tried to run Belarc Advisor to list all the contents of my system, and it came back saying it was running
Windows 8, AND an incorrect Name for the computer. And I KNOW I'm running Windows 10, and I DO know the name of my computer on my network.

Anyone? Anyone?

Do both of these drives contain ALL of your personal files--pictures, mp3s, videos, tax returns, etc?

Do they appear to be exact replicas??

dmholt57 said:

Right click on the Start button and select Disk Management. This will give you a picture of your drives, one says boot

Right you are, Texas.
Booting from C!
ONE mystery solved.

ignatzatsonic said:

Do both of these drives contain ALL of your personal files--pictures, mp3s, videos, tax returns, etc?

Do they appear to be exact replicas??

Hey, Iggy.....I'm starting to sound/feel more and more like I need a Martini.......

Turns out that what I THOUGHT was a duplicate copy of Windows was some folder that I'd had on my old PC where I'd "filed" a ton of sound effects and other stuff from a copy of Windows NT!!! (How the hell I got involved in that I can't remember....and won't waste my time or YOURS trying to.

So, no, I only have ONE iTunes music folder with my 10K odd songs in it and one Picture folder with my shots from the last 10 years..........THANK you for suggesting those folders as "tests" of duplication.
(The "friend" who put my old drive in my new PC for me didn't exactly do me any favours by leaving dupe programs on both drives......and by naming a new folder on my C drive "From old computer". I guess I should have paid a little closer attention!)

Getting down to some REAL/ACTUAL questions now.

Of the programs that I DO have duplicated, the Paintshop and Malwarebytes and all, is it safe to assume that anything that "comes up" on the Start menu is only ever located on the C drive? Or can the Start menu actually launch a program that's on a secondary drive?

AND, Along those same lines.....would I use Revo Uninstaller to delete those "superfluous" apps......or just grab and trash them within Windows Explorer?

RolandJS said:

If using Revo Uninstaller, because you have several duplicate programs, make sure it is actually truly aimed at the program you want to remove, use Safe scan mode. I do not recommend Moderate or Advanced scans, such might remove pieces of programs that you want retained.

Makes sense, thanks. But, can I actually "designate" a target drive in Revo?

I'd probably disconnect the "D" drive by pulling the cables inside the case.

And then try to find out what I COULDN'T DO--if anything. Do all apps pop open and run as expected with D disconnected? Can you find all data? Anything peculiar?

I'd probably try to operate that way for a few days.

If all appears OK, I'd then consider leaving the D drive right where it is (inside the case), reformat it, and using it as a backup destination for your personal data now on C. Unless you have a better use for it.