The purpose of the "Shrink" tab in the VMware Tools screen isn't to change the size of the disk as Windows sees it. Rather, it decreases the footprint of the virtual disk in your Mac OS home directory. Suppose you had an (ordinary, default for Fusion and Converter) 100 GB virtual disk, containing 75 GB of stuff. It would occupy a bit more than 75 GB of space in your Mac OS home directory, even though Windows would continue to see this disk as being 100 GB in size.

Suppose you then deleted 25 GB of stuff. The virtual disk would still take up 75 GB in your Mac OS home directory.

Suppose you then ran "Shrink". After that operation, the virtual disk would take up a bit more than 50 GB in your Mac OS home directory. As always, Windows would continue to see this disk as being 100 GB in size.

Is what you want to do to change the effective size of the disk (as Windows sees it), rather than the physical size of the disk (as your host Mac sees it)? I can certainly imagine Partition Magic helping with that. It could decrease the size of your C: logical drive, leaving behind what it would believe was "unallocated space on the physical disk". Of course, it's really a virtual disk.

So how to squish out that "unallocated space on the physical disk"? Well, that's among the things VMware Tools Shrink does. But you said you didn't want to do that.

Here's an idea: after you use Partition Magic, run VMware Converter again inside that VM. Converter writes virtual disks that are no larger than necessary. So you'd discard the original virtual machine and use the new one.

Caution: although I've used both Converter and Partition Magic many times, I've never tried this exact operation. So be careful, keep backups, Your Mileage May Vary, etc.

Either way works. Using VMware Converter to export to a smaller virtual disk works just like Ghosting to a smaller disk works. And separately, if you Shrink a VMware virtual disk and it's physical size on the host is less than 100 GB, you can run Partition Magic or the gparted live cd to "cap" the logical partition to 100 GB the dynamically allocated virtual disk will not grow beyond 100 GB. The "unused" virtual logical partition space is just an artifact of the virtual disk container not real "wasted space" as it would be a physical drive.