The design view grid is the smallest it should be. If you made it a 2x2 grid and then went into form view and made it a 1x1 and saved it, closed it, and when you opened it back up it should be a 2x2 again. That's not true for the bigger size though, if you have a 2x2 grid and open the form view to 4x4 and save it, it should open at 4x4 next time. So set the form view where you want it and Ctrl+S (save) it, it should open at that size when you back into it, unless the design view grid is bigger then the form view you set, then it will open to the design view size.

Regarding the second question of why the form looks bigger in form view, that's because the form has scroll bar and record selector enabled.  When the scroll bar is enabled, the form adds extra space at the right edge even when the scroll bar is not visible.  Disable it in form properties, and the form will have the same width in design view and form view.