The response I got was basically that this forum is too popular (a good problem to have maybe?)!
This forum is hosted with other people's websites on a single host computer, and so we all have the share the computer's resources (RAM) for our websites to function. A lot of RAM is used to process everything that everyone is doing on this forum, and unfortunately it's not the only website that needs to use the RAM to function, so at 'peak' levels of activity, Dreamhost actually has to throttle/limit the RAM it lets this site use so that other sites hosted on the same server don't get shut down entirely. So the site throws 500 internal server errors when the RAM is unavailable to process your post/click/query/etc., but that RAM might be available 1-2 seconds later, which is why the errors appear intermittent and unpredictable.
I apparently have 2 options to resolve this issue.
One is to "upgrade" to a virtual private server where I will (kind of) have a computer dedicated to hosting/running this forum only, so I won't have to share the RAM with other people's websites. This option could cost somewhere around $200/month, which is a cost prohibitive option for a non-profit/noncommercial website, even with the help of the tip jar (which is always appreciated, and does offset some of the server costs, but which was never expected nor intended to generate that kind of money!). And for the record, I have always and will always keep this forum & my finch websites advertisement-free, so commercializing the forum in an attempt to make it pay for its own hosting is also not an option.
The second option is to search through all of the code and processes of this forum, essentially, and look for any redundancies... anywhere where the "fat" of the behind-the-scenes processing that is so RAM-hogging can be trimmed, so to speak, so that the forum is more streamlined and doesn't need as much RAM. This is a HUGE, and I mean HUGE project that I am admittedly not equipped to undertake on my own. (I'm not a programmer unfortunately, though these days I really wish I was!!). But I'm trying anyway! I will go ahead and warn you now it might just take forever for me to resolve this issue, but I'm committed to doing the best I can, and I really appreciate your understanding in these matters!

In the meantime, I truly apologize for the 500 internal server errors. They are very obnoxious and I hope hope hope I'll be able to rid them eventually--which can't happen soon enough in my opinion!! But do know that they're not your fault
