This is terribly annoying one. After PD6->PD7 upgrade, whenever I'm opening one of my VMs by double clicking the VM package, PD7 will automatically open/start all VMs in the library. In fact, PD7 will even ignore what "Start Automatically" setting is configured to in VM's options and will start all VMs simultaneously even if "Start Automatically" is set to "Never"!. Grrr! Pulling my hair! That what you pay when getting into free beta-testing
Did you also update to Lion? Lion by default will open every window of a program that was open if you just quit the program, and restart the program and open the windows if you shut down or restart with the program running. If you are using Lion then either uncheck the "Open windows when logging back in" when you shut down/restart, or close your Parallels emulation windows before quitting Parallels.
