Recently wanted to identify how to turn off these default windows. Here is how to fix.

1. After you login, press the ESC button.
2. From the system menu choose "Character Configuration".
3. The 5th icon down, on the left, is UI Settings, click this.
4. If not selected already, select the "General Tab".
5. Scroll down to "Recommendations", deselect Show upon login.
5. Scroll downwards to "Playguide", deselect Open upon login.
6. Scroll to end and select the box for "Display achievements nearing completion as login notification. This feature appears to use reverse login than what would be expected.

Your done! Have Fun!