Mary, I think you need to realise that ‘upgrade’ in this case means overhaul. You’re either going to need someone who can analyse what you have already and write a script to import all of your content into a database or series of post requests, or manually copy/paste/re-design. If you don’t have many pages, this won’t be a problem, but it’s not a magical process of click a button and suddenly you have a dynamic site.
There may be a plugin or app out there somewhere which can help import a static site, but I would think that you’d really need someone to analyse the structure of your site and documents to ensure you import the correct content to the correct places.
As for 1) you can use all of that in a dynamic site, but you’ll need to plan for it as mentioned above and 2) you might want to consider getting someone to help.
Looking at your site, it seems like about 10 static pages and 20-50 pdfs/jpgs. It would take someone who knew what they were doing an hour or two to move the content into a CMS/blog. It would take longer to redesign and spice things up. If you want to have a go, just copy and paste and revise from there.