Regarding your second option, of creating a VMWare image... yes you certainly can. It is called a P2V (Physical to Virtual) migration, and you can do a hot clone, rather than a cold clone.
First, you need to put the original Windows 8 disk back into the machine. Boot it up.
Connect an external usb disk large enough to hold the Windows 8 installation, to the Windows 8 machine.
Below is an excerpt from Converting a physical machine for Fusion, Workstation, or Player using Converter Standalone
Downloading and Installing Converter
On your physical computer, download VMware vCenter Converter Standalone from the VMware Download Center.
- Double-click the installer file to start the installation.
- Select your language.
- Select the default installation options.
- On the Setup Type screen, select Local installation.
Converting your physical machine
- Start vCenter Converter.
- Go to File > New > Convert Machine.
- From the Select source type menu, select Powered-on machine.
- Under Specify the powered-on machine, select This local machine and
- From the Select destination type dropdown menu, select VMware
Workstation or other VMware virtual machine.
- From the Select VMware product dropdown menu, select the VMware
product you want to use to run the virtual machine.
Note: If the current version is not available, please select the previous available version. The virtual machine can be upgraded to the latest version in the VMware Product which you are using.
- Click Browse and navigate to the connected external hard drive or
SMB network share. Choose a location on that drive to save the files
and click OK.
- If you want, change the
name of the
virtual machine by editing the
Name field under Virtual machine details. Click Next.
- (Optional) Click the Edit button beside Data to copy to make
adjustments to the partitions you will import. If your computer
only has one partition, or if you want to convert the entire disk,
skip this step.
- Deselect the partitions that you do not want to convert.
Note: If your physical machine has a recovery partition, deselect this partition.
- Click Next.
- Click Finish to start the conversion.
Once the conversion process has completed, disconnect the external hard drive that the converted virtual machine is stored on and connect it to the machine that is running your VMware product (Fusion, Workstation, or Player).
In your case, you will take the original Windows 8 disk back out of the machine, replace it with the larger "Mint" disk. Boot into Mint, connect the USB external disk, start up the VMWare software and point it at the virtual disk image on the USB disk (or, preferably copy the virtual disk from the USB disk to the larger mint disk) and then run the Windows 8 within Mint.
To create a new virtual machine from the converted virtual disk files, see:
Fusion – Creating a virtual machine from an existing virtual disk in Fusion (1023555)
Workstation or Player – Creating a virtual machine from a system image or another virtual machine