We have a great resource that will help troubleshoot this issue. It may be isolated to third-party software or plugins, which would explain why uninstalling and reinstalling iTunes has not resolved your issue. For information, please refer to the following:
Thanks for your answer. I opened iTunes in safe mode, it worked and I started to listen to my podcasts again... Then it froze again.
Did the same thing a couple of times... and found out what was wrong!
I had a corrupted podcasted .mp3 file. I absolutely do not know why. This file can't be opened even with another player different from iTunes.
I removed this faulty file. Now everything is OK again.