The defaults for the search dialog can be set by going to TOOLS -> CUSTOMIZE -> Search (left hand side about half way down). Click on the + to open the submenus where you can set the defaults.
I’m not sure about the scrolling to end of file. I see it happens if I drag the scroll bar to the bottom, then the cursor does end up at the end of the last line (technically the end of the file). It doesn’t happen if I click on the down arrow for the scroll bar and scroll to the end that way. It does happen if I press the “End” key three times quickly to go to the end of the file. Hopefully someone else can answer this.