I can't really argue with anything above except that
(a) if it's relatively big and hefty, with a built-in DVD drive it's more likely to be called a 'laptop' ; but
(b) if it's lightweight and with no DVD drive it's more likely to be called a 'notebook' (or, if it's smaller still, a 'netbook').
This article is more dogmatic. While I can't wholly go along with it (because there are definitely some grey areas) it does give you an indication of the points that you need to consider when buying a portable computer - whatever it's called!
http://differvs.com/difference-laptop-notebook/