This question is about Lenovo but other brands are of interest.
What I want to do is the following:
1) Turn off Secure Boot so that DVD will boot OR boot from DVD anyway starting with Windows running. That much is OK as long as Windows is still working.
OR get into the UEFI settings to turn of Secure Boot. (how?)
2) Boot from DVD and create a hard drive image on an external USB hard drive for safe keeping.
..... then later:
We will assume that the internal hard drive has failed entirely or that I just want to wipe it out.
3) Boot from DVD and write the image from above onto the internal hard drive.
My concern is that one might not be able to boot from the DVD drive in order to do Step 3.
How can I force a Lenovo laptop to let me select the boot device when the hard drive or Windows isn't bootable? And, maybe Safe Boot is still turned on? Or, should I be asking a slightly different question?