in that the desktop they donated was very old and beyond its prime.
The game you have sounds like it is for System 9 (aka Classic) which does not seem to be fully functional on that Mac.
Perhaps you could contact your local Macintosh Users Group and ask them for help with this old system. Apple, or the Apple Store, will offer nothing in the way of help for it.
I'm a kindergarten teacher and for Christmas a parent donated a Mac desktop to my class. It sat empty for a long time, but I just got a computer game for it and I can't get it to install. It's compatible so that's not the issue. I put the disk in, click the installer icon, then a window comes up that says something along the lines of "classic is starting". Then it just stops. I've left it like that for hours and it does nothing. Any ideas?