Maximise Window

((System.Windows.Forms.Form)System.Windows.Forms.Form.FromHandle(Window.Handle)).WindowState = System.Windows.Forms.FormWindowState.Maximized;

Export Scene

To save a .jpg straight from Blender:

1) Set up scene.
2) Press F10 to jump to the scene tab.
3) Under the Format heading, click on the list box next to the “Crop” button.
4) Select jpg
5) Press F12 to render.
6) After it’s done, press F3 to open up the Save Image dialog.
7) Select where you want to save it and click Save.

from: http://forums.xna.com/forums/t/30640.aspx