It would help if you had the actual Blue Screen message.
Most likely candidates from a quick review of the Microsoft Knowledge Base are:
1. User account settings are corrupted (See
here for troubleshooting).
2. She removed Roxio Easy CD Creator 5 Platinum Edition (See
here for troubleshooting)
3. The computer is infected with a variant of the Sdbot virus (See
here for troubleshooting)
My recommendation is to first eliminate the possibility of a virus then go from there.
The problem is probably a missing driver or corrupted user account.
Missing or Damaged Driver FileUse Recovery Console to replace the missing or damaged driver file. To do so, follow these steps:
1. Insert the Windows XP CD-ROM into the CD-ROM or DVD-ROM drive, and then restart the computer. Select any options that are required to start the computer from the CD-ROM or DVD-ROM drive if you are prompted to do so.
2. When the "Welcome to Setup" screen appears, press R to start Recovery Console.
3. If your computer is configured for dual booting or multiple booting, select the relevant Windows XP installation.
4. When you are prompted to do so, type the administrator password, and then press ENTER.
Note In Windows XP Home Edition, the administrator password is\ blank by default.
5. At the command prompt, type the following command, and then press ENTER:
cd windows\system32\drivers
6. To rename the damaged driver file, type the following command, and then press ENTER
ren drivername.sys drivername.bak
where drivername is the name of the damaged driver file.
7. To copy the driver from the Windows XP CD-ROM to the Drivers folder, type the following command, and then press ENTER
copy cd-rom:\i386 drivername
where cd-rom is the drive letter for the drive that contains the Windows XP CD-ROM.
8. Type exit, press ENTER, and then restart the computer.
Missing or Damaged User32.dll FileUse Recovery Console to replace the corrupted or damaged User32.dll file, then, if needed, perform an in-place upgrade (also called a repair install) of Windows XP. To do so follow these steps:
1. Insert the Windows XP CD-ROM into the CD-ROM or DVD-ROM drive, and then restart the computer. Select any options that are required to start the computer from the CD-ROM or DVD-ROM drive if you are prompted to do so.
2. When the "Welcome to Setup" screen appears, press R to start Recovery Console.
3. If your computer is configured for dual booting or multiple booting, select the relevant Windows XP installation.
4. When you are prompted to do so, type the administrator password, and then press ENTER.
NOTE: In Windows XP Home Edition, the administrator password is\ blank by default.
5. At the command prompt, type the following command, and then press ENTER:
cd windows\system32
6. To rename the User32.dll file, type the following command, and then press ENTER:
ren user32.dll user32.bak
7. To expand a new copy of the User32.dll file from the Windows XP CD-ROM to the System32 folder, type the following command, and then press ENTER:
expand cd-rom:\i386\user32.dl_ c:\windows\system32
where cd-rom is the drive letter for the drive that contains the Windows XP CD-ROM, and c:\windows is the drive letter and folder in which Windows XP is installed.
8. Type exit, press ENTER, and then restart the computer.
If Windows XP still fails to start, you may need to perform an in-place upgrade (also called a repair install)
Hope this helps.