I don't understand why, but I can't quit emacs. When I do C-x C-c, emacs just says:

(No files need saving))
setq: End of file during parsing 

I need to kill emacs in order to quit.

I suspect that it might be a problem with ido, which I was using when this problem started.  I have deactivated ido in my .emacs, but now the problem persists. 

Any ideas of what can be causing this bug?

S.