For anyone else having much fun with this:
The good news is I found a fix for this since we had about 3,000 pcs having issues (drawback of having 2 common pc images - 1 for staff and 1 for student pcs!) after spending 13hrs on this yesterday.
After much following of blind alleys and cul de sacs etc I found that if you went to the BBC site as an admin, it'll crash the first time as expected but if I then re-visited it it worked fine and hence its why the realplayer fix appeared to work but in reality its not this that fixed it for me. I concluded that something was happening in that first crash which resolved it for the subsequent runs. This allowed me to take a snapshot of this process using win-install and thus I found:
The BBC site is forcing realplayer to re-register a whole load of HKEY_CLASSES_ROOT registry keys which in a locked down environment will cause an IE crash with an error code of 0xc000005 (access is denied). The keys I found either relate to the JRE's installed or Realplayer. As soon as I applied the registry file with just classes_root keys to a problem pc it resolved the issue and allowed normal operation of the bbc site once more incl. radio player etc. It is realplayer version dependant though so I have a version for 10.0 and for 10.5.
I deployed my fix via our Win-install scheduler service to our entire system and it seems to be working (fingers crossed, touch wood etc ;-) ).
I can post my registry file to anyone who wants it but you will have to modify it for your environment most probably.
Thanks to all who replied to my post,
PC Desktop System Administrator
University of Kent