Hide a view if less than N results
You could in a template preprocess function easily detect the number of results (rows) that a view has and set the output to an empty string if that is the case.

To get this to work, you might need to do a bit of work in template, as Views always adds some wrapping HTML that you probably don't want if the view is empty.

I would probably be easiest to do in the template_preprocess_views_view() preprocess function. You can consult the views interface to get hints about templates.