^^ sounds like your doing something wrong mate.
I have a library called Movies which spans three folders, none of which are on Drive C.... I just opened LIBRARY then rightclicked a space and did "new library" and then once named, rightclicked it, selected properties, and then added in my other folders.... is this what you're doing ?
As for the Start menu, not sure I understand your question, but I use the search function at the bottom to type in the name of the file or folder I want to find within my library and it fins it really quickly.
Oh, also you can add network folders to your library but you have to make sure you index the files first. I cant remember how I did this, think I just followed the help document it provided when...