how to make a boot disk for toshiba satellite c855d

(I made the DVDs using the Mac Disk Utility. I also tried burning downloaded disk images for Lubuntu 14.04 and PuppyLinux to DVD, but the laptop just boots right to Windows, even when I select to boot from that drive in BIOS. After disabling Secure Boot, the Toshiba will try to boot from USB, but I get either a black screen, or a short message containing 'prefix' that very quickly gives way to six white dots where the top of the letters were. I should have recorded all of the different tries, but they were mostly Xubuntu or Lubuntu LTS releases from 16.04 back to 12.04, and Puppy Linux. or may be in the original packaging but not sealed. The item may be missing the original packaging or protective wrapping. Computer Drives, Storage & Blank Media Hard Drives (HDD, SSD & NAS) US 78. So far, I've tried a number of distros from a live USB made on a MacBook using UNetbootin. Dell 15K HDD 6Gbps SAS 300 GB Internal 15000 RPM 2.5 ' ST9300653SS Hard Drive. I've decided that I'd like to put Linux on it to make it useful again, but I'm having terrible luck getting an install to happen.

Prior to me receiving it, that person forgot their logon info, so it's just been sitting collecting dust. This computer was awful on Windows 8.1 when the previous owner was using it. A while back, I inherited a Toshiba Satellite C855-S5303 (AMD E-300, 2GB RAM).

How to make a boot disk for toshiba satellite c855d