To import an iPhoto slideshow:
Make sure the DVD menu from which you want to access the slideshow is open in the iDVD window.
For example, if you want the slideshow to be accessible from the main menu of the DVD, the main menu should be showing in the iDVD window.
Open iPhoto and select a slideshow.
Choose Share > “Send to iDVD.”
After several minutes, a button for the slideshow appears on the menu. The button has the same name as the slideshow.
The slideshow also appears in the Movies section of the Media pane, so you can use it in other iDVD projects as well.
You can change the name of the button by clicking the button twice to highlight the text and typing a new name.