Maybe you had the same problems I had with Starcraft and Starcraft Brood War with the installation. Try to copy the Warcraft III Disks (both Reign of Chaos and Frozen Throne) into your computer before installing or duplicate. I think you can delete the copies afterwards (but if that makes a problem than don't delete them). For me, it worked for Starcraft. Maybe it will work for you as well.
Also, in the stores, the Warcraft III CDs they have a different computer system requirement than older Warcraft III disks 6 years ago. It could be your computer is "outdated". I know this cuz I had the same problem with the installation with my older computer before I had a new computer.
this is not help...
i installed on my laptop wc3 many times, but now after , reinstall windows vista and with new hard disk i cant install