Product list page only (thumbnail image, price and selection for all products on one page).
No categories.

Current Selection

Product list with links to product pages, which have a full image, price, etc. on that page.
No categories.

Category list page with links to category pages which list products in that category with thumbnail image, price and selection for all products in that category.

Category list page with links to category pages which in turn have links to product pages that have one product each.