i have one idea. try to delete all partitions when installing winxp. there is one option where you can delete, create ant manage your partitions. try to delete all and create new ones. it will automatically format it to ntfs, but you will lose all your files.
maybe the partition magic made some errors? maybe windows can't load with new settings.. strange.

edit --
there are some bootable "read ntfs" file systems like win98 startup disc. it loads modified DOS that can read files in ntfs filesystem. try to add one more hdd and to copy files from your damaged disc into new one.