Yep, you are doomed now. The only OS this laptop will ever boot is Linux from now on. Do not place it near other Windows computers, they may get infected.
Seriously. Windows setup will show you black screen when it does not understand your HDD layout. Try to boot up with a Linux CD and delete all partitions. If this does not help you may need to overwrite the beginning of HDD with dd to make sure Windows thinks it is an empty HDD.