QuoteNow, it is my understanding that I need to 'burn' the image of the OS onto the disk and then attempt to boot from that disk before I can go through the installation and setup process, what software do I need to burn the image?This why I suggested that you buy the disc or USB all ready for you to use - especially as you are having so much trouble with your system. I recommend doing so.
If you are set on burning your own USB then I recommend installing Unetbootin from http://unetbootin.github.io/ as it will download Ubuntu 20.04 (or many others) and burn it to USB all by itself. Painlessly. BUT I still suggest that you buy one in view of your system problems, especially as you have to await delivery of your new SDD, anyway.
Don't forget to change the PC's boot order so it looks for USB, DVD then hard-drive/ssd in that order.