Doc apart from the above question, there are better ways we can get a handle on your "State of The Nation".
If you have everything plugged in, and then from Terminal in your Sylvia Cinnamon type and enter
... that's a lowercase L ... and print the output that is a good start.
Or there is GNOME's Disks which is on your Mints.
I'll print a few shots and explain a little on each (some will expand a little if you click on them)
SCREENSHOT 1 - WIZARD IN SEARCH OF GNOME DISKS
Start by clicking Menu and then start to type in "disks". Choose Disks.
2 - WIZARD'S SOLID STATE DRIVE 256GB
If the pics are hard to read (tiny), try holding down your Ctrl button and at the same time tap the + button a few times, you can return to normal with Ctrl - 0 (zero).
This pic shows my SSD in the Dell laptop, where Windows 10 and 6 Linux Distros reside. I have clicked the disk on the left to highlight it, and clicked "OS" which is Windows in the main part. My free space shows at the right. Note that the Windows system, which you might be used to as the C: drive, here, is /dev/sdb3
3 - WIZARD'S (INTERNAL) SATA HDD - 2TB
This pic shows my 2TB HDD in the Dell laptop, it's a Seagate, and I have highlighted /dev/sda1 which houses a Linux Mint you will be familiar with. The drive is temporarily partitioned as MBR - Master Boot Record, while I run some experiments. After they are concluded, I will return it to the GPT (GUID Partition Table) it came with.
Under MBR you can only have a maximum of 4 partitions, so if you want more (for more Linux, of course) you have the first 3 as Primary, then the 4th as Extended, under which you can then create Logical Partitions to house more. An MS-DOS/Windows limit, not Linux.
4 - WIZARD'S EXTERNAL HDD (WESTERN DIGITAL) 4TB
This pic shows where I house most of my Linux Distros on the Dell "system".
Long story short - Doc, what I am hoping is you can provide us with pics similar to the above, highlighting the status quo of the 2 Samsungs and the Toshiba, we will have a clearer picture.
And I bear in mind about how the WD Blue SSD 1Tb internal will replace the Toshiba 320GB?
If it is your plan to "port" Win 7 to the WD Blue - have you got a Recovery Plan in place? Installation disk or image on USB stick?
Cheers
Wizard