I am working to help a charity that receives computers cast off by hospitals and schools. I don't want to have to install Ubuntu on my own desktop in order to get access to all the download features for a bootable USB.
Is it possible to download the whole program in a bootable/installable state onto a USB key so that I can use it to install on another computer, often one with a password protected and time-limited blocked Windows OS, in order to completely install Ubuntu over Windows?
Yes.
The ISO file you use to create a LiveUSB should be checked for download errors following http://tutorials.ubuntu.com/tutorial/tutorial-how-to-verify-ubuntu#0 , the 'checksum' process which runs the values of the downloaded ISO file through a formula. If you 'check' the 'sums' and get the save value as the original ISO file has, they the ISO file arrived completely correct.
Installation, as per Canonical, Ubuntu's publishers, is typically done following these instructions on a Windows PC https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-windows#0 using a 4GB or larger USB Flash Drive. You don't need to install Ubuntu onto your PC to do that.
1) rufus.ie is a Windows app which should be installed as any other Windows app. It does not go on the USB key.
2) Ubuntu is put on the USB key by running Rufus after you have downloaded the ISO file of Ubuntu Desktop.
3) I am not sold on Etcher being better than Rufus, and neither is Canonical, the publishers of Ubuntu, because their tutorial says to use Rufus. Some folks like Etcher because it's not Windows-only.
Once you make a LiveUSB, install it following these steps https://tutorials.ubuntu.com/tutorial/tutorial-install-ubuntu-desktop#0.
