How to boot and install Linux or BSD on a 2007 MacBook White via USB?
I personally installed FreeBSD on a G4 machine via USB, so I don't see why you can't do that with a 2007 MacBook.

But going back to the original question


  is there a reliable way to boot and install Linux, BSD, Windows (anything not OS X)?


Yes.  There is a site called Linux on Laptops (I linked the Apple section) that outlines what laptops are compatible with Linux.    Specifically for Debian, they have a Wiki that describes exactly how to install it on a Mac.

As mentioned before, I am partial to BSD.  FreeBSD has USB images specific to UEFI machines available for download.  

There is also excellent HOWTOs available to assist you in this process.

As for your "Bonus Question"...


  Bonus points for running the OS live from the USB -- since after 10
  years HD may fail some time soon.


Why would you do this and not replace the hard drive? 

A SATA1 interface is 1.5Gb/s

A USB2.0 port is 480Mb/s

Rough math tells us USB is 1/3 the speed of a drive.  A brand new SanDisk SSD is less than $50 online.  It doesn't make sense to sacrifice that much performance for that small price.