iPhoto's Web page export isn't particularly flexible, although it's fine for basic Web pages. There are workarounds for some of its limitations, though not for others.
Web page export tips:
iPhoto doesn't let you add a line of descriptive text to your thumbnail page, as iWeb photo pages do by default. If you know a little HTML, you can easily add text to that page using a text editor.
If you select a background image instead of a color, iPhoto tiles the image under the thumbnails. That can work well if the image is large and light colored, but avoid using small, dark background imagesthey make for a cluttered presentation.
Assuming you have a permanent Internet connection (like DSL or a cable modem) and an IP address that never changes, you can make your pages available on your Mac by turning on Personal Web Sharing in the Sharing preference pane. If you have a permanent Internet connection but not a static IP address, you can learn more about how to work around this limitation with dynamic DNS. See www.technopagan.org/dynamic/ for more information. Also consider using iPhotoWebShare, webPhoto or myPhoto (see "Other Web Export Tools" to the left) to serve your photos directly.
If you feel as though you're wasting a huge amount of time fussing with Web pages exported from iPhoto, I encourage you to check out Apple's .Mac service (www.mac.com). iWeb's integration with .Mac works very nicely.
Other Web Export Tools
There are many other tools for generating Web-based photo albums. I can't list them all, but this collection will get you started. For more utilities, search for "iPhoto" on VersionTracker (www.versiontracker.com). Beware of old and potentially incompatible plug-ins!
FlickrExport by Frasier Speirs; free. iPhoto export plug-in for uploading to the Flickr photo-sharing site. connectedflow.com/flickrexport/
BetterHTMLExport from Geeks R Us; $20. iPhoto export plug-in for making Web pages. www.geeksrus.com/software/betterhtmlexport/
ShutterBug by XtraLean Software; $49.95. Drag photos in from iPhoto; full-featured; neat Web slideshow. www.xtralean.com/SBOverview.html
iPhotoToGallery by Zachary Wily; free. iPhoto export plug-in for uploading to Gallery-driven Web sites. www.zwily.com/iphoto/
PictureSync by Holocore; $14. Imports from iPhoto and uploads to many Web services. www.holocore.com/?PictureSync
webPhoto by Alex Johnson; free. Provides a live Web interface for browsing your entire iPhoto Library. www.ionize.org/webPhoto/
iPhotoWebShare by bitpatterns; free. Easy to use preference pane that serves iPhoto albums directly. www.bitpatterns.com/iPhotoWebShare/
myPhoto by Michael Mulligan; free. Serves iPhoto albums directly with no exporting. http://agent0068.dyndns.org/~mike/projects/myPhoto/