live usb - How to create a bootable USB stick?

I am looking at this:
http://www.ubuntu.com/download/help/create-a-usb-stick-on-ubuntu

I need to create a boot disk to test Ubuntu to make sure it will run on a PC (Compaq Mini CQ10-120LA) I was given. I can create the boot disk off of a Mac (in English) or Windows (but Windows is in Spanish and foreign to me).

Questions:

1. What format do I choose for the USB stick? (I wish the instructions stated this).




2. What is Dash? (Will I know when I run the installer?)




3. Can I do this from a Mac or Windows computer? Or only from Ubuntu?