Kind of weird. Maybe you should refer to my "Do You Believe in Ghosts" post. How did this come about, Carl? Did you just turn on the computer one day and it was hosed up? What version of Windows are you running? Has there been a recent Windows Update? Notorious culprit for anomalies. If so I'd try a System Restore to a time before any updates and see what happens.
I run Win7 Pro 64 and a week or so ago, while using Office 2003 Pro, sentences started highlighting themselves for no apparent reason. Then the page became unusable. Sure enough, a Windows Update had occurred that very day. Restore fixed the problem and that's the last Windows Update I'll ever do. Just a thought.
jsapair