The DR-DOS/OpenDOS Enhancement Project

Regards EDR-DOS, you need to install DR-DOS 7.01 first then install the updates for "Enhanced DR-DOS" from this site.

I do not know all your answers, but generally speaking modern printers, scanners and sound chips do not work as in the main need Windows Drivers.

glennmcc.org/download/masrtin/page2.htm

On modern PC/Laptops many have ditched either serial or paralell ports.

Therefore to set up a system anywhere near you requirements you would IMO need older used hardware.

Though I wholeheartedly agree the **-DOS was great in its day, a Linux solution may be the answer as an alternative, sorry Udo !