Lightroom :: What PPI Should Be Used When Exporting For Video Project

I shoot RAW photos.  I like and use Premier Elements 11 to make video.  Frequently I insert photos in the videos and enjoy using the Pan and Zoom technique (frequently credited to Ken Burns).
 
Resizing photos support Premier Elements to run smoothly.  The LR Export command makes it easy.  Using PSD files works well in Premier Elements.  However, I am confused about settings.
 
My understanding is that if no Pan&Zoom or cropping is to be done in the video the export should be 1920x1080.  If Pan&Zoom is planned, the setting should be higher by about 50%.  LR makes it simple by letting you specify the "Long Edge" so the setting would be 2880.   The short edge will match the original. 
 
What about "Pixels Per Inch" for a HD 1920x1080 video project that may be played on a big HD TV or smaller YouTube?  There is plenty of information about PPI for printing and computer monitors, but not HD Video. 
 
Here is screen capture for reference:

What should the pixels per inch be set at to match 1920x1080 video?  The 140 setting is a complete guess!