What is the best virtual hdd format to convert to ISO?

[LightningShock]

Hello, I want to create a bootable stick with Lubuntu(by the way I posted this on a generic forum because I feel like it doesn't matter), so I want to install this OS on a VM, convert its virtual hdd into iso and inject that iso into my stick.
When I was creating the hdd for the vm, I was shown many options(vdi, vmdk, vhd, hdd, qed, qcow if I spelled them all correctly) so which one should I use? Something tells me that I should use vhd but idk.
Sorry if I have a bad English...

[mpack]

This topic does not belong in "Using VirtualBox", since it doesn't concern a VirtualBox UI feature. Moving it to "Linux Guests".

I suspect that you have a fundamental misunderstanding of what an "ISO" is. It's an image of a data CD/DVD, nothing more. Hence it is impossible to have an ISO image of a hard disk. Installers come on ISOs (or actual DVDs) because someone wrote an installer for the file set in question. He didn't just copy it to CD.

So, your actual question is meaningless.

On the other hand, hard disk imaging for backup/restore purposes is not new, it just never involves ISO files. Recommendations for which disk imaging software to use in this case I'll leave for Lubuntu experts to give. You really need an imager which runs inside the guest and which understands your guest's filesystem.

[Perryg]

Actually this will not have anything to do with VirtualBox since you can not boot from USB in VirtualBox. You can make a bootable USB issuance of *Ubuntu and they have detailed steps to do so. Just ask or google create bootable USB for Ubuntu.

[mpack]

Perry, I don't think he's asking about booting from USB in VirtualBox. The OP seems to me to be describing a V2P migration, i.e. he wants to boot physical machines from USB, using a Lubuntu image which originates as a VirtualBox VM. I assume he wants to play with Lubuntu before settling on a image to use.