Posted this in another forum and got what I believed to be the perfect answer I was looking for:
Go to the shortcut for any of these programs, right-click and select 'Properties', select the 'Shortcut' tab at the top, and next to 'Run:' change the setting to 'Maximised'.
Wordpad and DAP are now fixed. But...this works if you open a NEW notepad file..but if I create a Notepad document, save it, then re-open it is still not maximised (however Wordpad does for some reason).
Thanks for your help