You are better off not trying to expand the hardware abstraction layer dll to grab the file... there are about
seven of them and they are selected based upon the configuration of your hardware. However, Dell may only have one present since their laptops hardware is fixed. I am guessing this is the correct one: Halaacpi.dll
I would backup the hard drive
before doing anything.
Did you try restore from safe mode if it is accessible?
If the first part of
kleinkinstein's link does not work here is
another help from MS.
If it doesn't work
a repair install will need to be made, but this is hard to do on a Dell as a matching OEM or retail XP version must be used as the recovery CD that comes with the PC cannot be used and will destroy any data on the drive.