when i run it, it just goes to a black screen with the little white line and nothing happens

Run videotest.

Have you tried to run the game in different graphics settings? (Double click on the d2vidtest file in your diablo 2 directory and change the options there)

a few things that may help you:
Try running the vid test and check, if you get any errors, post them
Intall the latest patch
You could also try playing in windowed mode.
or else it can be something with you graphic card
if nothing helps try to re-installing the game

This post was edited by JokerGuy on Jun 14 2011 04:03pm

a tip for those who cannot launch the game in full screen mod, you have to tick those lines :

http://i53.tinypic.com/15qs229.png