iTunes repeatedly freezes/quits responding on launch

Every few months iTunes goes into "not responding" mode when I try to open it, I have to go into Task Manager to close it. It doesn't even show up on the screen, the tab appears at the bottom of the screen and then nothing. I've followed the troubleshooting suggestions to start a new library (on the third one now) and rebuild, it works but I have a lot of podcast episodes and it gets really annoying. Any suggestions how to stop this?

Windows XP, iTunes 10.7.0.21 (tried "upgrading" to 11 and it immediately froze, actually come to think of it that might've been when the problem started), between music/movie files and podcast episodes I have about 3,000 items. Any help would be appreciated!