Q. I have 2000 fonts. Can Mac OS X handle them?

A. Mac OS X can handle them without a font manager or tool like ATM. If you have many fonts it's easier to use a font manager. SuitCase and FontReserve both have Mac OS X compatible versions available.

There's also Font Agent Pro, available from Insider Software. Very iTunes-like UI, which makes things easy.

Q. How do I prevent users from installing their own fonts?

A. Make their Fonts directory read-only. From the CommandLine:

[localhost:~] you$ sudo -s 
[localhost:~] root# chown root /Users/username/Library/Fonts 
[localhost:~] root# chmod a-w /Users/username/Library/Fonts 

Q. Is there a way to see all the characters in a font (similar to double-clicking on the old font file in OS 9)?

A. One way is to download the freeware XFontInfo and then assign it as default application to open fonts.

Another way (at least under 10.2, not tested in earlier versions) is to turn on the built-in Character Palette. This gives you a Pop Char-like menu (for fans of the old DA) at the right of all application menus with some nice features for saving favorite characters and searching for available ones. Go to System Preferences -> International -> Input Menu, and check the box.