Can’t get MacBook a1181 to boot
Not all A1181's are the same. A list of the specs for various A1181's are given at this website. Other than some being black and others being white, here are some other differences.


Early models have "Core Duo" processors. These are 32 bit machines. These machines can only run 32 bit BIOS or EFI booting operating systems.
Middle models have "Core 2 Duo" processors. These are 64 bit machines, however the EFI is still 32 bit. These machines can run 32 bit or 64 bit BIOS booting operating systems, but only 32 bit EFI booting operating systems.
Later models have "Core 2 Duo" processors with 64 bit EFIs.  These machines can run 32 bit or 64 bit BIOS booting operating systems, but only 64 bit EFI booting operating systems.


It would be helpful if you could list the ID and/or family for both Macs.

According to the website, possible IDs and corresponding families for the A1181 are given below. 

    ID                        Family
----------     -----------------------------------------
MacBook1,1     (13-inch)
MacBook2,1     (13-inch, Late 2006), (13-inch, Mid 2007)
MacBook3,1     (13-inch, Late 2007)
MacBook4,1     (13-inch, Early 2008)
MacBook5,2     (13-inch, Early 2009)


I should also note that some early Macs needed a firmware update before being able to run BIOS booting operating systems. See: About EFI and SMC firmware updates for Intel-based Mac computers.

Note: BIOS booting normally does not require a MBR table. However, Intel Macs require a well formed MBR table in order to BIOS boot. This does not present a problem when using BIOS/MBR arrangement. Many BIOS booting Linux distributions use a BIOS/GPT arrangement. If you choose this arrangement, then you must hybrid partition the boot drive. This is a firmware requirement, even if the booting operating system will not use the values stored in the MBR table.