This one is a little embarrassing to report, because I’ve been frustrated with it and just living with it so long. However, maybe it will help a few of you out there.
For a very long time, I’ve been getting regular script errors in IE7 on Vista. I assumed that it was some artifact of the additional security that Vista provides and I just decided to ignore it. Finally I got frustrated enough to try to fix it, and boy is it easy. Just make sure that the setting ‘Disable script debugging (Internet Explorer)’ is checked in your Internet Options / Advanced tab, as below.