There are a number of ways, depending on how and in which program you've created your slideshow.
Assuming you've resized your photos to 1000x750 and you've unchecked the preference for Scale to Frame Size BEFORE you imported the photos into your project:
* You can use the pan-and-zoom presets on your photos just by dragging them from the Effects panel.
* Or you can manually create a pan & zoom for one photo, copy it, select all of the other photos on your timeline, right-click and select Paste Attributes.
If you created your slideshow in the Elements Organizer, you can select the option for random pans and zooms to be added to your slides.
If you are in Premiere Elements 10 Windows and not using the program's Pan and Zoom Tool, the suggestion is to apply a pan and zoom effect to the one photo.
Then, select that photo, Edit Menu/Copy. Then, select all the photos that you want to have the same pan and zoom effect.
Now Edit Menu/Paste Attributes.
There is no "Apply Pan & Zoom to all Slides" for this as in the Photoshop Elements Elements Organizer Elements Slideshow Editor preferences.
I suppose you could create your slideshow in Premiere Elements 10's Elements Organizer Create/Slideshow so that you
could use this "Apply Pan & Zoom to all Slides" for the pans and zooms, and then use theElements Organizer Slideshow Editor's Output option "Edit with Premiere Elements Editor" to get the slideshow into the Premiere Elements workspace.
If you are using Premiere Elements 10 or 11's Pan and Zoom Tool, then please check out my blog post on the topic of applying the same pan and zoom effect to more than one photo.
Add On...I did not see SG's reply until after I had posted mine.