We have two computers and we have Warcraft-III and Frozen Throne. My son is using reign of W-III original disk and I use W-III:FT disk. You can play Frozen Throne if you have any.
My son is playing on Battle.net and I decided to try as well, but when I tried to log-in, I got a message saying that "the CD key provider is currently in use by *MyPCName*, when I start using it, my son has the same message... We have of course different accounts. Is there a way to play together on the Battle.Net??