From Word Help:
Use smart paragraph selection Select this option to select the paragraph
mark when you select a whole paragraph. If you include the paragraph mark
when you cut and paste a paragraph, you don't leave a blank paragraph, and
your formatting automatically stays with the paragraph.
Use smart cursoring Select this option to specify that the cursor moves as
you scroll up or down. When you press the LEFT ARROW, RIGHT ARROW, UP ARROW,
or DOWN ARROW keys after you scroll, the cursor responds at the page
currently in view, not at its previous position.
Note that although Help is far from perfect, in the Word Options dialog box
it actually gives you useful information (just press F1 with the dialog box
open).