Did you restore the iPhoto program? or the iPhoto library?
If you restored an older version of the iPhoto program them simply install your latest version from the disks - either the restore disks that came with your computer or the purchased upgrade disks - remove the iPhoto receipts first
reinstall iPhoto - go to your receipts folder ("Your hard drive" ==> library ==> receipts) and remove any iPhoto receipts and reinstall from the restore disks that came with your computer - do a custom install of bundled software only
For more information <a href="http://www.macworld.com/article/132243/2008/02/pacifist.html"> click here for the MacWorld article on reinstalling OS X applications.</a>