You can modify the photo grid on a photos page to allow for more or less text for captions, or you can turn off captions completely.
Select a photos page by clicking it in the sidebar on the left of the iWeb window.
Click a photo on the photo grid to open the Photo Grid window.
Change the number next to “Caption lines” to the number of lines you want to allow below every photo on the page.
To turn off captions for all photos you’ve added to the photos page, set the number of caption lines to zero.
Type your captions in the placeholders below the photos.
To edit an existing caption, select it by clicking it, and then type a new caption.
Note:You can’t edit the text (the title of the album and the number of photos it contains) that appears below album thumbnails on an albums page, but you can hide it. Click an album to open the Media Index window, and deselect the “Show title” and “Show number” checkboxes.
The caption and title settings apply to every album on that page.