I would advise you to update your Norton AV definitions. However you can manage it, get Norton working again and run a full system scan - the more i think about it, the more it sounds like a virus infection. If you visit Symantec's website, you can find a support page where you can try to fix your Norton problems.
When did script error start to happen? Did it happen the same time that your Norton AV stopped working by chance? And just exactly what is going on with Norton? Does it not respond when you try to update your definitions?