That is some heavy software.
I would suggest removing it and then reviewing the exact installation instructions.
You could try entering the Main Administrator account at the Welcome Screen by pressing:
Ctrl > Alt > Delete twice and choose Administrator.
Here, if it loads, you can try System Restore.
Or you can try removing Norton from
start Control Panel > Add/Remove Programs
If none of the above works Norton issues special uninstall programs as their software is so intrusive into Windows.
We can look that up by designating your exact product.
Just for example:
http://service1.symantec.com/SUPPORT...01092114452606
Inserting your own version into search should bring up the details.
e.g. uninstall norton xyz