I have a few subscribed subs there for self hosting and a few other subs related to Linux and the sort. (I know the fediverse has those too! :) ) only because the majority of new updates or announcements for selfhosted apps and tools are made there only.
I used to be a mod and stopped posting during their protest and haven’t posted since. I also ran a userscript to delete all of my posts and it seemed to have scrubbed my history correctly there. I’m a lurker there and their new design really has gone to heck. I have uBlock origin and AdguardHome running on my network and their pages don’t play well sometimes with errors displaying what I assume to be ads.
The CPU speed setting in the BIOS would help certainly. I would always set mine to the higher speed when it gave me the option.
More or less, the Turbo button was useful for the older software which couldn’t handle the ability to run faster or ran too fast. Depress the button to toggle the speed down or up. (Nice little read about these here) https://dfarq.homeip.net/why-did-old-pcs-have-a-turbo-button/
As for the HDD since you were able to write a file, it’s probably fine. One item of note, HDD’s are not considered permanent storage as you have natural degradation of the magnetic layers on the surface (a.k.a. bit-rot) which is what you are probably seeing with the corrupted files. Simply formatting the drive should be enough for it to refresh the drive’s platter(s) and create a more viable readable and writable surface. HDD’s will be more prone to failing via motor or controller board failure. You really have nothing to lose other than a little bit of time! Then, if it fails during Win95 or Win98 install, then yeah, replace the drive.