I use Adobe Type Manager, where I created groups of fonts for different occasions.

My 'basic' set, that is active all the time contains only ~100 fonts. Not even 100 fonts, but 100 files. For example "Arial", "Arial Bold", "Arial Italic" are three files, but only one font in different appearances.

Then there are sets for 'customers', 'rarely used' and so on.

The nice thing about ATM is, that you can activate / deactivate your fonts / sets at any time, even while you are working, without restarting the application.
This goes for Win2K, but I think it works the same in Win98.

I think that a lot of fonts really slow down your machine, but most of all, it would be bad for my workflow to scroll through hundreds of fonts all the time ..

Wolfgang