Hers another way of doing it using photosuite 8.
Open photosuite go to file and click on new canvas that will open the select canvas screen select custom size if not already selected go down to units and select pixels then enter the correct aspect ratio
4:3 720 x 540 NTSC
768 x 576 PAL
16:9 848 x 480 NTSC
1024 x 576 PAL
Click ok then click save as i saved mine in a new folder in My Pictures as VW 8 scanner background.DMSP
this allows you to scan you photos at there native size you then open the above saved project change the background color go to insert photos and cutouts resize the inserted photo to suit add edge fading,shadow etc.,save as a jpeg and then when you insert it into VW it's at the correct aspect ratio. It works great for portrait photos as you can have two one the one slide.