Not sure if you've researched stuff very far, but they make a wide variety of keyboards you can use and some are metal instead of plastic. Or a harder plastic. Think they're called "mechanical". They require a bit more force to hit the keys, and a usually super loud compared to the modern keyboards, but they're a joy to type on for people that are used to it. My favorite keyboard is actually an ergonomic one from Dell from the early 2000's, and I'm pretty sure it's a mechanical sort, since it's super loud. It's one reason why some of my typing habits are how they are - which hand hits the "y" for example - since the keyboard's divided in half. They also make keyboards that come in two halves, so you can space them as far apart as needed for your arms. There's also some I've seen that have different key types that you can swap out.
I think you can. Sorta. It's just making yourself write the things that keep distracting you. It may take a few days, even if it's just summarizing the ideas down. At least that works for me: take a few minutes to write the ideas, then the over active muse shuts up 
On the topic itself - I have very little self confidence in my writing. Not that I'm not any good in the actual practice of writing, thoughts, characters, story, blah blah. But actually having readers interested enough to do more than silently read. I recall the best I could choke out of someone who read one of my stories was "I think they need counselling". The world is falling apart around them and you think they need counselling?! Really?!
It's very annoying because I have that kind of feeling that is "I have to tell this story or I'll suffocate underneath it."
