I am completely new to this and I have a few questions. Also I am very dense, so with that being said please offer explanations as if they were being presented to a class room of third graders during their show and tell, right after snack time

1) First machine is a 2010 MBP with a 2.3 GHz Intel Core i5 processor, outside of tweaking settings within FAHControl is there a way to optimize this setup to dedicate more oomph?
2) Second machine is a Dell Inspiron, how would I go about stripping it down in order to optimize it to function strictly as a folding machine? It has a 2.4GHz Intel Core i5 processor.
3) The first machine runs high sierra, and the second machine runs windows 10, would I be better off running some Linux Distro on these babies instead?
4) My current ISP is X-finity and imagine it will be for the foreseeable future. They provided me with their equipment (ARRIS TG1682G) this was ~3 years ago. Any suggestions as far as investing in my own networking equipment, is it worth it in my specific case?
Forgive the cha-cha like questions, and thank you for the help!