Hi

To try and break this down into smaller chunks...

You can either (both if you have enough USB sticks) RUFUS / VENTOY to create the installer.

Start with a fairly easy Distro like MINT  and check it's not corrupted if you wish.

The ISO will drop onto the VENTOY USB without any decompressing/extracting.

Rufus will possibly check the ISO for validity/veracity as it is on an option screen.

Next YOU MUST ENSURE that Windows has released it's hold on the HDD/SSD

ANY/ALL fast start up options must be OFF, and a CLEAN shutdown is essential, no Hibernate or Sleep at all.

Next would be to boot from the USB and observe the options available.

Mint will run LIVE without installing, so that it can be assessed before choosing to install.

Windows normally has 4 partitions, BOOT, hidden, C:\ and REcovery.

Linux can/will install GRuB into that same BOOT partition alongside Windows.

Then the other partitions are / (root) /home (optional, but recommended) and SWAP (optional).

If in doubt please ask.

Thanks for the responses!   Resetting the BIOS and using a Dell image seems to have worked!

Prego.