I'm not sure, but today we have actually launched a thread for just these issues. It's possible that it's Java related, but I don't have a definite answer for that.
I have the HT-BD2T and love the system. It has played every Blu-ray I have used (over 35 titles) except Mad Men Season Two. The discs will load and then freeze the first 2-3 seconds or just continue to load indefinitely. The stop and eject commands will not work and I have to shut down and restart the unit to be able to command the disc again. I have firmware 1.4 installed, have replaced Mad Men Season Two with other copies including one directly from from Lionsgate. Is the problem Java related, will there be another firmware update and why won't the discs load?