Well, 98 isn't really good for that type of active service. Second, such a service would have to be resident in memory at all times, thus using up precious CPU and RAM on an already limited machine. So, sure, I could do that, but it's not a good solution.
A better solution would be something like extending autorun so that if it is attempting to run an AOL disc it simply fails and ejects the disc. It would be stupid, but at least it would not have to be a resident process. That would also be dependent on my being able to decompile autorun.exe, or rewriting it from scratch, or maybe renaming it to autorun_native and then writing an autorun that would simply detect AOL and die or invoke autorun_native.
Either way, that is an attempt to save people I tried to help from doing things I specifically told them not to do.
Now that I think about it, that autorun wrapper I described above is a decent solution if one had to be written, though it may have to be updated for each new release of AOL depending on what conditions it use for verifying AOL or not.
Of course, it would not be able to stop someone from just going to the disc and running setup.exe.