To skip to Battle.net and run in a window, all you need to do is:
Step 1:RIGHT-click on your Diablo 2 SHORTCUT. It needs to be the shortcut, as it has a target line area in which you need to edit some things.
Step 2:After the right click, go to Properties, and open it up.
Step 3:In the Target area, where it says C:/Program Files/DiabloII/DiabloII.ink or whatever you have(mine is not installed at the moment, so I cannot be sure) you will put a -w for windowed mode AT THE END OF THE COMMAND LINE. This is very important. Also, it needs to be OUTSIDE of the parenthesis. To skip to battlenet, it is the same thing. After you put -w, hit space and type -skiptobnet. This will run your Diablo 2 Normal or Diablo 2 LOD in Windowed mode and it will immediately skip the intro and the main menu and go right to the battle.net logon screen.
=) Have fun!