Try Ron Martel's method
<quote>
Identifying the cause of STOP errors using PSTAT & Excel

Many times when a STOP error occurs the information provided does not
specifically identify the application, device driver, or other
component file where the error occurred.  However the 4 parameters
associated with the STOP (bugcheck) code will very often include one
that is the address where the error occurred.  You first need to look
up the detailed information about the specific STOP code in order to
determine if the address is included and if so which of the 4
parameters has the address.

You can identify the meaning of each of the parameters for your
specific STOP code at:
http://msdn2.microsoft.com/en-us/library/ms789516.aspx

The second step in the procedure is to identify the addresses that
each active process is being loaded at.  The PSTAT utility will
provide this information.   On some systems the PSTAT utility may
already be present.  Check this by opening a Command Prompt window
(Start - Run - CMD) and entering the following command:

PSTAT /?

If PSTAT is not on your computer you can download it free from
Microsoft.  The download is called "Windows XP Service Pack 2 Support
Tools" and it is available from
http://www.microsoft.com/downloads/details.aspx?FamilyId=49AE8576-9BB9-4126-9761
-BA8011FABF38&displaylang=en
With PSTAT installed on your computer the next step is to open a
Command Prompt window again (Start - Run - CMD) and generate a report
with PSTAT.   Because you need to copy part of the information from
this report (and only part) it is best to create the report as a text
file.   In the Command Prompt window enter the following command:

PSTAT > C:\JUNK\PSTAT.TXT

You may change C:\JUNK\ to whatever drive and folder that you want to
save the report into.

Now open the saved file in Notepad.   Start - Run - NOTEPAD
C:\JUNK\PSTAT.TXT

Scroll down the file, about 80% of the way to the end of the file and
you will find a head line:

 ModuleName Load Addr   Code    Data   Paged           LinkDate

It is the information from this line to the end of the file that we
want to copy from this file and save as a separate file.  Select the
block of text and copy it to the clipboard.  Open a new notepad window
and paste the clipboard contents into it.   Save this file under a
different name.  I use PSTAT2.TXT and put it into the same C:\JUNK
folder.

Now launch Microsoft Excel and use File - Open to bring the PSTAT2.TXT
file into Excel.  Excel will automatically parse the file into
columns.  Once this is done use DATA - SORT to sort the entire
spreadsheet based on the value in Column B (Load Addr).

It is now a simple task to read down the addresses until you find the
highest value that is less than the address where the error occurred.
That module (name in column A) is the prime suspect for the cause of
your error.

Good luck

Ron Martell     Duncan B.C.    Canada
</quote>

Alison, try this fix
            http://support.microsoft.com/kb/916595

Alison

What appears in the lines below:
0x000000D1 (0x00000000, 0x00000002, 0x00000000, 0xEFB3E7FC).

Does the error occur on start up or later. Are you conscious of doing
something, which lead to the error?

Background information on Stop Error message
http://msdn2.microsoft.com/en-us/library/ms795930.aspx

0x000000D1: DRIVER_IRQL_NOT_LESS_OR_EQUAL
The system attempted to access pageable memory using a kernel process
IRQL that was too high. The most typical cause is a bad device driver
(one that uses improper addresses). It can also be caused by caused by
faulty or mismatched RAM, or a damaged pagefile.
Source: http://aumha.org/a/stop.htm

http://www.microsoft.com/whdc/devtools/debugging/installx86.mspx

Are there any yellow question marks in Device Manager? Right click on
the My Computer icon on your Desktop and select Properties,
Hardware,Device Manager. If yes what is the Device Error code?

Try Start, Run, type "sigverif.exe" without quotes and hit OK. What
drivers are listed as unsigned? Disregard those which are not checked.