Diablo 2...good times good times...if only DIII would be out already
IIRC that color bug is connected to the anti aliasing
setting. Switch it off and you should be good to go.
I just checked the properties..this is how i have it set
Here's something I never tried myself because I didn't have the need for it:
Here is how to fix it without playing in Window mode
Just alt tab out of Diablo when you start it and open Task Manager (Ctrl+Shift+Esc). Under the Processes tab find explorer.exe and End Process it. Alt tab back to Diablo II and the colours should be normal :P That's how it worked for me. If you want to start your explorer.exe again: Task Manager-> Processes-> File -> New Task (Run...) -> type "exlorer.exe" and hit enter
Hope it helps!