Hal.dll error is a pain in the butt! Firstly, your XP disc needs to be at least SP2 otherwise it will not work, and secondly, XP can only format 32GB in FAT32, so if you chose a partition bigger than this, XP would have automatically formated as NTFS.
The HAL error (Hardware application layer) is very hard to get rid of because it can be a plethora of things wrong causing the hardware anomally - trust me!
You can try the following though - this is supposed to work, although I have not personally tried it, but have tried getting rid of the HAL.DLL error on a windows system and it was a nightmare and I build and fix computers:
Do NOT remove or alter the partition created with BootCamp assistant in the Windows XP installation progress. Just choose it in the installer and format it.
Step - By - Step:
* Start up Mac OS X and run the BootCamp assistant (Applications / Utilities)
*Remove your old Windows partition by choosing to merge the parts back to one.
*Run the assistant again and allocate the space you want for Windows
*Get the Windows XP CD and put it in.
*Choose to install Windows now and reboot the computer.
*Boot from the CD by pressing and holding the “c” after the start up sound.
*Go on normally until you come to the partitioning.
*Select the partition called BootCamp and hit enter. (DO NOT REMOVE IT).
*Choose a full format in the file system of your choice.
*Proceed with installation as normal.
Let me know if it works.