@maxthrottle :- Hallo.....and
to the "kennels".
Whilst generally speaking I agree with @rcrsn51 about the need for older Puppies on older machines - there ARE limits, even for Puppy! - I've had success booting Fossapup64 9.5 (the original build) on an elderly Dell Inspiron 530s desktop, circa 2007/8.
I would hazard a guess this is a Vista-generation machine. My mate's 530s has almost identical specs to this; I think his Pentium Dual-core is the next model up (an E2180, I believe; the 2.00 GHz model), and he has 2 GB RAM.....but that had no problems with booting from CD.
I couldn't get it to boot from USB, due to the fact that the ancient BIOS in that machine doesn't recognise the way that modern USB flash drives now report themselves as a USB-HDD; newer BIOS implementations will now recognise this, and will work with it. Unfortunately, there are no further updates for that machine; it's already on the newest BIOS available for it.
I KNOW for a fact that I've had Xenialpup64 successfully installed AND booting on that machine. Worth a look, perhaps:-
https://distro.ibiblio.org/puppylinux/puppy-xenial/64/
However, @bigpup may be closer to home. Windows 'burner' software doesn't always create a bootable Puppy disk correctly; sometimes it's the software itself.....but more often than not, it's down to user error, and not understanding a few simple, basic rules when burning an optical disc.
Mike. 