I installed Windows Vista (32MB) using Parallels but want to try out VirtualBox because I've had some issues with Parallels. I installed it but don't know what to do for the "Hard Disk" option. Can I somehow have it reference the Windows (partition?) since it is already installed? Right now, when trying to play the virtual machine, it gives the following error message: "FATAL: Could not read from the boot medium! System halted." Thanks for your help.