While using iTunes to play through an album that I hadn't listened to all the way through before, I found iTunes unexpectedly quitting about one second into one particular track. I relaunched and verified that it was that particular track that would crash it. Assuming the file was corrupted somehow, I grabbed the original CD and re-ripped that track. Same problem. I have a registered copy of Audion from before I started using iTunes, so I tried ripping the track with that. At that point, the track played fine, but when I matched the tags from the previously ripped version, it again crashed iTunes.
Now, I should mention two things: the album in question is a cast recording from a musical, and I like to list every featured singer on a particular track in the Artist field (I have a couple of Smart Playlists that grab every track on which a particular singer performs, and I have lots of cast recordings in my collection). This particular track had about nine names attached to it, some of them particularly long names. When iTunes ripped it, it automatically fed the same tags in, since I had entered the tags before ripping the album the first time. When Audion ripped it, it left most of the tags empty.
On a hunch, I trimmed the Artist field for that track down to just the two most primary singers and played it again. This time, no problem. So it was definitely the too-long Artist tag that was crashing iTunes. What I think was happening is that when iTunes tries to load into its display the Title, Artist, and Album tags, if one of those tags is beyond a certain length, it just doesn't know what to do, and so it just crashes. This is in iTunes 4.0 on Jaguar 10.2.6; I don't know if the same bug still exists in 4.0.1 or 4.1, or in Panther.
So if you have a track that is mysteriously crashing iTunes, check to see if one of those three key tags is too long, and trim it if it is.
Mac OS X Hints
http://hints.macworld.com/article.php?story=2003111118475620