You see the problerm is, as far as I can find, that the 1525 is too old to have secure boot. Is the choice in the BIOS? What does the label on the bottom side of the laptop say for model number?
O.K. so with the computer off plug in the Hiren USB flash drive, press and hold down the F12 key as pressing the power button, hold the F12 down until the boot menu appears (have you run the "Diagnostics" from this menu at some point?) then select "USB Storage Device". What happens? A screen shot would be helpful.