Terminal won't open after mistakes made with using fish shell (dont know how to undo my error)
 

I've been fooling (that's too true) around with fish shell. And now when I try to open gnome-terminal or terminator, I can see them try to open but close immediately.
I was trying to login to bash and then drop into fish via bashrc. When i ran fish from .bashrc it worked fine but started very slowly. So went into gnome-terminal configs and added fish startup as a startup command. This seemed to work ok but when I then opened mc there was a lag of maybe 10 sec delay. After trying to cancel the startup command, terminal closed immediately and terminator wouldn't open.
I thougt maybe something could be fixed through dconf but I don't have a terminal.
I realize I probably deserve it but I hope someone can help me resurrect my terminal access. I don't want to have to re-install if I can avoid it.

If you have a working Desktop Environment, you can make a new icon for it for gnome-terminal or xterm. Then modify that icon so that the command it executes is something like this:

The Gnome Terminal should also work with the -x option if you prefer that.

Then you should be able to use Gnome Terminal directly.

If that doesn't work, maybe try ctrl-alt-f1 and switch to a console and use dconf from there?

Which files did you change manually?

I'm afraid this is a very bad solution, almost the worst possible solution. (the worst would be to buy a new house with a new computer with a new os in another city).
Anyway, you can remove your .bashrc file (or better to just comment out lines) (or whatever file you changed) to see if that helps.