On the new Acrobat, there is no setting to change the default for this. It defaults to ON at all times. I am a legal professional, and this would be a big improvement for me. Users who regularly navigate long PDFs of hundreds of pages or more would benefit from having this setting OFF when opening documents, instead of having to disable it every time. As a side note, to my mind, a selection available from the current settings SHOULD achieve this, but currently does not - see attached. There is currently no difference that I can discern between Single Page and Single Page Continuous. Single Page should disable scrolling, or there should be a separate option.