Hi,
The "Unable to find bootable option" is comparable to a defective hard drive in a computer: It will still do the initial start-up and then be unable to do any more. The recovery tool still recognizes the phone when connected, but is unable to install the operating system in the phone when it comes to that. Again comparable to booting a PC on the install DVD and then be unable to complete the install.
The phone needs mechanical repair. If it is out of warranty, then is is also beyond economical repair, unfortunately.
If it is still in warranty, then please consult the point of sale.
--
Hans