For your 'script error' try this: With IE open, click on Tools, click on Internet Options, and then click on the Advanced tab. You should see a heading that says Browsing, and under that, one that says Disable script debugging. If there is not a checkmark at this, put one there.
For your HJT, close all windows, scan with hjt, and have it fix the following entries:
R3 - Default URLSearchHook is missing
O2 - BHO: (no name) - {029CA12C-89C1-46a7-A3C7-82F2F98635CB} - (no file)
O9 - Extra button: Help - {1EDF7E86-71C9-4A9C-BD7A-36BE465AEAFF} - http://www.btopenworld.com/helpbb (file missing) (HKCU)
O18 - Protocol: aim - {3050F406-98B5-11CF-BB82-00AA00BDCE0B} - %SystemRoot%\system32\mshtml.dll (file missing)
O18 - Protocol: shell - {3050F406-98B5-11CF-BB82-00AA00BDCE0B} - %SystemRoot%\system32\mshtml.dll (file missing)
This will just clean up your log a bit. Post another log as I'm sure there are more things that should be addressed by one of the pro's. When you post the new log, include whether or not you still get the script error.