Windows Explorer Extremely Slow

Windows Explorer on my wife's computer (running W7 Home Premium and completely up to date with Windows Updates) takes 4 or 5 minutes to finish running right after a power-up boot. The hourglass icon seems to sit there forever, but the folders and files finally appear. Later, when running an Explorer-type function, such as saving a file in Word or opening a file in some other application, a long delay occurs again. Her computer hardware and software components are very similar to mine, and I never have this problem. She may have a few hundred more photo files than I have, but I can't identify any significant difference. During these long delays I've watched the Task Manager, and no appreciable amount of processor time is being used. Is there something I can monitor or log to find out where this time is being spent?

--Jim--

Under the Performance tab of Task Manager click on the "Resource Monitor" button. That will show you what your CPU, Disk, Network and Memory are doing along with what all the different processes are using.