I found this interesting https://www.youtube.com/watch?v=59hVaIjxMIM but people say it does no longer work on recent Windows version. Also I don't like to install random binaries from Mega or similar.
In the end a realistic reactor simulation would probably to complicated for the layman, anyway.
try Nucleares (on Steam), it's a heavily gamified one but does cover various important aspects, including Xenon poisoning. You can find some play videos on YouTube.