If you have the original disc, 7.5.5 as you mentioned. Try the following. Insert it in your PC and try to determine the format father drive and see if it is the same as the one you burned.
The good news is that your optical drive is working as expected which is great!
Yes, if you suspect it is due to the disc type used then please try a different type but first checked the format of the original disc and compare it to the one your burned.
I think we are getting there but the HFS might be the missing piece of the puzzle.
—Alex
PS Keep me in the loop