If you get an error regarding a missing or corrupt hal.dll file, it might simply be the BOOT.INI file on the root of the C: drive that is misconfigured
  1. Insert and boot from your WindowsXP CD.
  2. At the first R=Repair option, press the R key
  3. Press the number that corresponds to the correct location for the installation of Windows you want to repair.
    Typically this will be #1
  4. Type bootcfg /list to show the current entries in the BOOT.INI file
  5. Type bootcfg /rebuild to repair it
  6. Take out the CD ROM and type exit