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#21
Imaging: normally used to restore a system after a semi-catastrophe. You make an image file while the system is running well. The image file represents an entire partition or drive and is stored on some other drive, usually external. You "restore" that image, typically after booting from a "recovery" disk that is made within the imaging app.
Cloning: a realtime transfer, without an intervening image file. Normally used to transfer a system that is running OK to a larger new hard drive. It's a "move" rather than a "recovery" from an image file.
Some imaging apps will also clone; others won't.
Imaging requires a storage space for the image file. Cloning doesn't because it is done in real-time.
Either might work in your situation.
That OEM partition is very very small. You might have to use a specialized app to look inside it. I would plan on transferring it to the new system unless you know it is either empty or useless.
Yes, it matters if the SSD is lower capacity. That's why I said you should try to shrink your C partition so that all of your partitions combined are smaller in size than the SSD.