I am at the login prompt but nothing comes up on the screen when I type my username

so now you're pretty much locked out completely?

then I'd suggest --

If you have stuff in that box you want to save then if you have some sort of medium (external/internal with cable hdd) then boot it with a live USB OS (Linux maybe) then hook up the medium to a different USB Port copy everything you want to save. Then wipe it and start over and do as I suggested before, give yourself a name and password you will remember or get a different Distro that has root and when you install that one use a split system.
in what ever order you want to slice it up. This way if something like this happens again you can save your home and wipe the system and reinstall with the same distro or a different one. Still being able to use your /home with everything already in it.

You'll just need to learn about config files and how they effect the wm/dt - basic stuff really.

you should be able to see your username, but there will be no visual feedback when you type your password, i.e. you type your password "blindly".

From what you are describing it sounds like Xorg and the GUI are either broken or badly misconfigured.

I strongly suggest performing a fresh installation of Ubuntu 16.04.

Right. Fresh install it is then. Thank you all for your time

Let us know if the fresh installation is a success:-

The fresh install seems to be working out ok. Didn't take very long. My faith in ubuntu has been tarnished somewhat by this experience.

that it perfectly ok. their are plenty of different Linux/GNU distros left to pick from.

1 members found this post helpful.

Glad to hear that the fresh installation is running well.

Maybe give Debian a try........

Don't forget to mark your thread SOLVED.