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
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.