Sorry for the confusion with #5 Carol, we must differ a bit.
If you just see the "inches" as illustrated below, perhaps you can change your measurements in preferances to be pixels.
However I found this wonderful site that might help you it is Jay Arraich's site tips:
http://www.arraich.com/elements/pse_ppreBeginner1.htm
The image is from his tutorial.
I hope you figure it out, Geary has really walked you throught the site stuff. Once it clicks, you'll never forget how to do it anywhere.
Good luck!