Just had to register my disappointment with macs in general and pretty tragic experiences with Parallels V6. I am a serious mac and P.C. developer. Got my Server 2008 virtual machine up and running and was hoping to use my lovely IMac to develop on both but experience all manner of issues with parallels and have decided to abandon the P.C. development on the mac altogether. not sure if people have had these but: 1. plug in certain usb hard drives and parallels crashes with its opaque screen of death so I have to reboot the mac completely. 2. had issues lately where the memory has run out on the virtual machine and it again crashed with the opaque screen of death and had to reboot. Managed to get to the configure screen eventually as it kept trying to restart the vm again and thus kept killing the mac. 3. lost the vm completely 3 times now, no good if you are developing whatsoever. sorry if I am whining, love the build quality of a mac but this coupled with nas drive issues and internet issues in Lion now i'm giving up. Andrew.
The behavior you are reporting is not normal. Opaque screen of death means kernel panic. That means something went really wrong. Take a look on the system logs from the crash (there should be something here, pointing to the right direction), but personally i think you have faulty RAM or CPU (put them on stress test, if the machine will freeze/panic, you have faulty HW). I never used PD6, only PD7, but all USB devices, network (even weird configurations (one VM as router for other VM's)) is working flawlessly.
I am forced to go back to straight PC. I am a MAC man since 7100 Power PC days. Unfortunatly I have issues with updates causing the PC side to crash, also 1 freeze with time machine doing its top up, VM crashed. I've had to reinstall twice. The Imac is acting slowly now, I will separate it and run a stand alone PC computer for the user. FYI its a 27inch Imac with an SP2 XP running inside. Needed Xp to run the boss's favortite software.