I've used Acronis for this job, but you can probably use a different bare metal backup program.
Remove the Virtual machine additions, if any.
Backup your system from within the VM.
Restore to a physical harddrive. You might have problems with the kernel, and device drivers being different in the VM than in the physical machine. A rescue disk of your distro can usually be used to fix those, with some manual work.
You're probably better off saving your data and doing a reinstall of the system, then restoring your data.
Last edited by mostlyharmless; 07-01-2010 at 01:40 PM.