HP DV7-6135x Laptop refuses to Use TI 2012 Bootable Disk

HP laptop DV7-6135x, Win7, DVD player, 8Gb memory.
Have used TI2012 to make complete backup of hard drive that needs replacing due to SMART Error 301 Imminent Failure. Backups successfully made. Disk Check shows disk is still OK, no errors. Also made boot ISO image. However, testing the Acronis TI 2012 Bootable disk first (Plus pack also installed on PC).

I changed BIOS to use the CD/DVD for boot. However restart keeps booting to the hard drive, not TI disk. What do I do? I need to change out the hard drive within several days and return it or I will be changed for the warranty replacement of the hard drive.