VMware Workstation locking up computer

amy

I have a strange problem that I think began after upgrading to  7.04 from 6.10 (Edgy.)  I am running VMware Workstation.  My virtual machines were all working flawlessly on Dapper and Edgy (and indeed on every version of Linux I've tried over the past couple years.)  Recently, however, i'll be running a virtual machine and my computer will lock up tight.  I have to press the reset button on the tower to reset it.  This happens with several of the virtual machines.  My Windows 98 SE virtual machine can reboot and log in before it locks the computer up.  My Windows XP Pro virtual machine was paused and can run for awhile before locking the computer up for apparently no reason.  Recently, I was trying to install Windows Vista and it locked up during the installation.  I cannot pin down whether it happens due to disk access or what.  In an attempt to solve the problem, I tried downloading and installing the new VMware Workstation 6.0 but the same problem occurs.  Previously I was running Workstation 5.5.  Has anyone else had this problem?  Any ideas of what to try?  Thanks.

*bump*

Come on guys, someone has to have some idea....

The  community is supposed to be the best!