Not clear if you have BSOD (black screen of death)
Try this -
Laptop on. Put in XP disc. Switch off laptop immediately. Laptop on.
Press any key. appear. If so ; do it;.
When you get to hard drive screen. Select and delete all partitions you can see (normally just C)
May have to press Advanced (sorry doin this from memory)
Then create a new partition to do fresh install