Glad it helped a little

I know this stuff sounds very confusing. I'll try to make it simple.
Please watch my video here, as I think this might help you a lot:
"What are we made of?"
https://youtu.be/uQV0bD8QIxgThe industry makes it more confusing because of arbitrary 'cutoffs' to define certain market segments.
I'll answer your last question first: 2nm is smaller than 100nm. (nm = nanometer).
In most cases, when we use the term 'mineral' we are discussing something that is actually based on an atomic element... a single atom, and every atom is far smaller than 1nm. Magnesium, potassium, calcium, etc. are all elements that we refer to as minerals, and we also often refer to them as electrolytes. There are more. Also note that oxygen, mercury, silver, hydrogen, lead, etc. are other atoms that
Some elements can float around in our bodies as a single atom... which we usually refer to as an ion, and many float around as a pair. Our body is very dynamic, so most things don't stay static for very long ;-)
The idea of 'nanoparticles' is mostly marketing hype. Its nonsense and should be ignored most of the time. Most things moving around in your body are nanoparticles... all the minerals, histamine, uric acid, etc., and we simply never talk about them as nanoparticles because it serves no marketing purpose. SO2 is a nanoparticle, but that is not relevant either. What is most relevant is if something is bioavailable or bioactive, and that happens at all different sizes. Proteins and other cells have an enormous range of sizes. And minerals.... well, they usually come 'trapped' in complex structures that may or may not be available to us. A mineral complex might be huge, and yet it might 'shed' it resources readily for our body to use, so size doesn't matter too much.
Context is everything, so let me give you some examples:
1. Most people have toxic ionic lead in their bodies. We never use the term nanoparticles when talking about lead toxicity; however, most lead toxicity is ionic lead that is less than 1nm in size. By contrast, clay contains lead, but that lead is not bioavailable because it is bound up in the clay, and thus cannot cause toxicity. The same is true for aluminum and other metals that are toxic to us in a toxic state.
2. Amalgam fillings have mercury in them, which is highly toxic. However, that mercury is bound up and does not often leech out into the body; however, if you have methane SIBO you are probably leeching quite a bit of mercury from this fillings! So again mercury itself is less than 1nm, but it must be released in a toxic form before it can harm us. Fish don't die from high mercury levels because they tend to have high selenium levels that bind the mercury. (I consume mustard seed and brazil nuts to get selenium, so that I have better protection from mercury poisoning).
3. Colloidal silver is a mix of silver ions and silver nanoparticles. Everyone markets their 'tiny' nanoparticles, which are hundreds or thousands of times larger than the silver ions! This is one of the most comic examples of how ridiculous the marketing is. Once again, size does not matter so much, because the 'huge' nanoparticles are clusters of hundreds or thousands of silver atoms, and the nanoparticles shed those atoms as silver ions under the right conditions. Decades of experience have showed us that homemade 'ionic' silver and all the various 'super special' silver nanoparticle solutions show no difference in efficacy... because they mostly end up as the same thing in the body. (However, I can make many arguments that the cheap homemade ionic solutions are far superior. Jason has much written about this too).
Not sure if I helped you understand or made it more confusing, but I tried ;-)
I do have more videos on this topic, and my videos show pictures of atomic structures, so that might help. Here are a couple of other videos that might aid you in understanding:
Fat vs Cancer
https://youtu.be/L5GS16b3tYMThe Power of MSM
https://youtu.be/r9yZwt90_lgEnjoy!