I can never seem to remember this line, so I've decided to put it here. If you want access to the BIOS in VMware Fusion virtual machines so you can change the device boot order and so forth, add the following line to the machine's .vmx file:
bios.forceSetupOnce = "TRUE"
When you reboot the VM will load the BIOS configuration screen without you having to frantically press a command key like F2 or DEL. When you reboot, the default behaviour returns.
The problem is, Fusion VMs are configured by default to boot from the hard drive first then the optical drive, meaning once you've installed an OS it ignores booting from the optical drive entirely. This will let you take care of this.
Grilled cheese sandwiches have cheese.