It logs into Ntbtlog.txt
Enable Boot Logging
ntbtlog.txt
C:\Windows\Ntbtlog.txt
To find that answer you would need to enable boot logging in the bios of the system you are operating with. To do this process a step by step can be found at: http://www.watchingthenet.com/how-to-enable-boot-logging-for-fixing-startup-problems-in-windows.html Typically the issues lay with the file AFTER the one that was previously loaded in the log as the system has already loaded the file in the log and crashes loading the one following.
The boot password is a feature provided by the motherboard (hardware) and is not stored in a file on the disk that WindowsXP could access.
Q: What is the recommended size for the boot file system? A: The /boot file system is recommended to be 50MB.
Boot Logging
Windows Boot Manager (bootmgr)File,Windows boot loader (winload.exe)File and the Boot Configuration Data (BCD) File
C:\Windows\Ntbtlog.txt Page 774 - Guide to Managing and Maintaining Your PC (7th Edition)
NTLDR is indeed a key boot file in Windows 2000 and all of the Windows operating systems since Windows NT. A machine will not boot without that file.
boot the system you need the file to be in, and navigate to the other systems folders.