With sadness I have to report that it doesn't seem to have been the problem.
You realise about 5,000,000 people, in the Greater London area alone, are having this exact same problem? Try Googling:
you either have Java Script switched off or an old version of Adobe's Flash Player. GET THE LATEST FLASH PLAYER HERE
There's probably a quick, simple solution. The main thing is not to do anything drastic. As it's a major problem the internet's now infested with entrepreneurial nerds trying to make money out if it, and giving complex 'advice' involving getting knee deep in registry files and God knows what else after, of course, you've bought their wretched, and probably useless or damaging, product. Avoid like the plague.
Are all your Java buttons ticked in your browser(s)?
Internet Explorer:
>> Tools
>> Internet Options
>> Advanced
Tick Java boxes, restart browser
Firefox:
>> Tools
>> Option
>> Content
Tick Java boxes, restart browser
You may need to reboot the machine to get the full effect. Finally, have you cleared the cache and then re-booted?