It looks like I'm going to have to think about making the smaller leap to OS 9 from 8.6, (instead of X), because fewer and fewer app upgrades (like Flash MX) will work with 8.6. I seem to remember, when OS 9 was released that there was a small utility that would check a hard drive to see what was and was not compatible with 9.
I've been using the Mac almost everyday since 1985 and always upgraded my Mac's systems, even if they weren't always that stable, but OS 8.6 is the most stable system I've used and hate to start in on troubleshooting another one in the midst of trying to actually get some work done (I think that's was computers were meant to do, help you with your work, not make you spend 1/2 your day troubleshooting!).
Does anyone know where I can find this utility? I've checked MacFixIt, and a few other sites, but can't seem to find it.