I have the same problem. I have used iTunes for years with no problems. When I installed v10.5.3, it constantly froze. I uninstalled and reinstalled with spotty success and then next time I turn on the computer--freezes again. Today I installed 10.6 and the same thing is happening. If I go into my iTunes library, I can play one song at a time! I am ready to convert all to mp3s and use a different player.
I've been using iTunes happily for about a year with my iPod. Last week, iTunes started to freeze up and ''not respond'' every time I would try to do something with it.
It wouldn't play songs, it wouldn't play the songs I would download. Now, if I can get it to open up, iTunes opens to one specific song title and then freezes up and does nothing else.
One error message I received guided me to apple's support page and there it indicated that quitting suddenly could be fixed by removing Quicktime and repairing iTunes. That did nothing. I've even removed iTunes and installed a new version, but the same problems continue.
I have an HP PC running XP media center 2004. I have a feeling that the problem is something with the computer as compared to the iTunes program. Any suggestions would be greatly appreciated.

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