I think there is a problem with the current implementaion of the top menu - at best its a bit confusing, at worst its frustratingly impossible to alter without editing the code.
essentially, there are two separate top menus available out of the box
one is fixed and includes :
Home page, New products, Search, My account, Blog, Contact us
the other appears if we choose to add categories or topics to the top menu - the result of doing either of those things is that the out of the box menu vanishes.
when it vanishes, we do not have the ability to add the home link, blog etc
I dont think it makes sense to have these two separate menus
I have written a bit about including topics in the top menu
https://www.nopcommerce.com/boards/t/35912/we-need-to-be-able-to-create-drop-down-menus-for-topics-in-the-top-menu.aspx
we should have just one menu - the contents of which could be edited via admin
the categories can be added to this as they already are
topics also can be added as they are (in forthcoming 3.6) - but of course with the suggestions i made in that other post :)
However, it would be practical to have an admin interface where we can choose the items to be included in the top menu (as i said, categories and topics can continue to be done in their own place)
it could be done in a simple way by providing textboxes (where we type the actual page name) and a corresponding display title (i'm thinking it could be a similar grid to what we use to add product attributes ?)
It would need to include a display order for each item - the display order would also need to take into account where on the menu the categories and the topics appeared in relation to the other items.
as a starting referance, have a look at nop-templates mega menu plugin