If you have a look on her homepage, she has laid it out like a shop window (which is what I alwayss recommend and tend to do on most of my site builds)
What I mean by this is, not only do you have a navigation link to each category, you also have a section on the home page with a little write up and a small image of a category product. Then when you click on either the image or the link, the visitor gets taken to that category page. So no pop ups on the home page.
Visitors to websites may not be the most *****est tools in the box... so you have to provide them with more than one way to access your products if possible.
Then look at this category page
http://www.beadedjewels.biz/jewelry_sets.html
Now when you click on each image you get a pop-up larger version. These are easier to clear from your screen to carry on shopping than a lightbox image is.
Also note next to each image is a description and price and buy now button.