Why does indesign cs5.5 keep shutting down?

Before i start - Im going to be honest im not great with computers. I'm using indesign cs5.5 (which im new too - to make things worse) im trying to delete a page that i have already worked on but no longer need but i keep getting theses messages -

What am i doing wrong?? Its the first page of the doc as i want it to start with double page - hope this is making sense.

thanks in advice