You have to be more specific on what transpired from the last time you used iTunes to the time it refused to startup for us to make an educated guess. In the meantime try deleting your iTunes preferences and if that does not work, reintall the app.
well i can't remember the last time i opened up itunes...maybe a week ago when i burned a cd...it was working ok at that time...now when i click on it...it takes a little while before the unexpectedly quit window appears...ahhh...you're talking to a newbie here...how do i delete the preferences?
On your question on how to delete prefs, you can easily do a Finder search for "itunes" (without the quotes) and delete any file that is located in the preference folder. Better than deleting, just move the file to another folder (just in case you want to revert to the old prefs). What version of OS X and iTunes are you using? [Edited on 6-5-2004 by elbertc]