Wow--interesting question! My first response is this:
1) An electronic form of "books." If I am limited to five items, then 5 books would not be enough. But if I had a Kindle, perhaps, I could have whole libraries of books on there. I think we need to remember history and learn as to not repeat the same mistakes. Included in these books would be the important, ancient historical books (including the Bible) and also books that tell "how to" (i.e. how to use herbs to make medicine)
2) Not sure if technology would be available in this new world, but if so, computer would come with. If not, pen and paper to write.
3) You said that all basic needs would be provided for. If the food was limited, though, I'd want to bring seeds and some animals. Can that count as one thing?
4) I would say people such as family and friends, but you said "things" in your question and since people are not "things" I'm assuming that my family is already coming with me for the sake of answering this question. If I'm thinking about personal comfort, I'd want to bring pictures--but not sure that would help develop a new civilization. How about some clothes and blankets, bedding, etc. There's personal comfort again.
5) What would be best for the good of all humankind? This question is more difficult than I thought. If food and shelter is already taken care of, maybe a bag full of things for cleanliness and personal hygiene? Toothpaste, shampoo, soap, etc. Then we can study its properties and figure out how to reproduce it.
I don't think I really like my answers. Oh well. I guess here's what is at the surface!