STOP CLASSIC FROM LAUNCHING WITHOUT PERMISSION

If you're just making the migration from Mac OS 9 to Mac OS X, one day you'll be doing a search for a file you created last year. You'll find it, then double-click on it, and since it was created in a Classic application on your old machine, it will boot Mac OS X's Classic mode and launch your old Mac OS 9 application. My bet is that you don't want to open that application in Classic (unless you absolutely have to). That's why you might want to have your Mac ask you if you really want to start Classic. To turn on this helpful warning, go under System Preferences in the Apple menu, click on the Classic icon, click on the Start/Stop button, and then choose Warn Before Starting Classic.