As part of the purchase, the user also upgraded to the latest VMware Workstation, version 8.x. The users RHEL4 guest was transferred over from the old laptop (running an older version of Workstation). It powered up and ran just fine on the new hardware / version of VMware, with the exception of the guest shutdown.
It literally took an hour from the point where the RHEL4 issued the halt to the underlying hardware (i.e. the OS portion of the shutdown is done) to a fully stopped virtual guest. From an appearance stand point, the VM screen turns black and remains that way until it fully stops.
The laptop hard drive indicator was also flashing madly during the entire process.
I found suggestions to prevent virus scanners from scanning .vmdk files, that didn't change the behaviour.
The laptop also uses PGP whole disk encryption. Perhaps Workstation 8 and PGP don't play nicely together? I couldn't find any references. The old laptop (much slower than this) also had PGP with the older VMware Workstation, so PGP didn't seem to be a prime candidate.
I eventually discovered this post on the VMware message boards that provided the solution.
The thread discusses a similar issue happening in VMware Workstation 6.0.4 on Windows XP.
The solution was to add the following lines to either the global VMware config.ini file, or each individual guests .vmx file. Exit out of VMware Workstation before modifying config.ini or the .vmx files
prefvmx.minVmMemPct = "100"
mainMem.useNamedFile = "FALSE"
mainMem.partialLazySave = "FALSE"
mainMem.partialLazyRestore = "FALSE"
With that code added to the configuration file, the virtual machine shuts down immediately after the operating system issues the halt.
Placing the code in the config.ini file affects all virtual machines, new and existing, unless the settings are overridden in the individual .vmx files.
For Windows 7, the config.ini file can be found here
C:\ProgramData\VMware\VMware Workstation\config.ini
For Windows XP it can be found here:
C:\Documents and Settings\All Users\Application Data\VMware\VMware Workstation\config.ini