Thanks for the help. It would be nice to not see the border, just a little cleaner and more realistic to visualise a mobile layout for a website. (you can work in Photoshop without a border)
My document is something like 640 x 4000 px so when I Shift-W that won’t be much help.
I tried creating the following script that puts Indesign into presentation mode at 100% zoom. But as far as I’m aware you can’t scroll while in Presentation mode so alas this isn’t quite the solution I was looking for

main();

function main()
{
try{

app.activeWindow.screenMode = ScreenModeOptions.PRESENTATION_PREVIEW;
app.activeWindow.zoomPercentage = (72/109*100);
}catch(e){}
}