I've used Joomla! for many years now. However, I'm planning on redesigning a couple of my websites and I don't need a database. CMS can be quite weighty and therefore you got to pay a lot of attention to get everything to load quickly off. So since I'm only offering articles and no forum I just want to use normal HTML which will load very quickly. Can someone advise me on the best application to use from this website. I was thinking of maybe the responsive design package would probably be most appropriate. But then there's another one, something to do with bootstrap.

I would definitely go with
https://www.coffeecup.com/carts/giant-super-pack/

I use all the software in this package. If you just wanted one app then I would definitely go with:
https://www.coffeecup.com/designer/

which software is best ?

depends on what you want to do