After a BSOD (graphiucs driver related) my NIS has a red cross in the taskbar and the interface has 'System Status: At Risk' at the top. The large yellow 'Fix Now' button has appeared below and when I click it it runs the LiveUpdate service which tells me that I'm completely up to date and a 'Fix Now' window also appears which sits there processing indefinitely. If I click on 'ok' in the LiveUpdate window the FixNow window stops and says Item: Protection Updates, Status: Not Fixed.
I don't believe I have any viruses but prior to my BSOD whenever I started Firefox I got a message saying that 'malicious exploit kit website 4' had been blocked. Following my BSOD upon automatic restart of my pc, NIS was disabled and it wouldn't re-enable until I restarted my machine manually.
Also, now whenever I try to go to something like hotmail or even my Norton account (by clicking on my account in the NIS interface), I get a message from Firefox saying that the connection is untrusted and that it can't be confirmed that my connection is secure.
What do I do? 
Edit: My subscription is current (if that helps) and a complete system scan revealed nothing