In addition to the above advice:
Is this a desktop or laptop? Which model & model # of HP computer have you?
If a desktop, if you can't run the HP recovery program, you can try to re-set the BIOS.
If a laptop, if you can't run the HP recovery program, I have no useful advice.
The HP recovery program will probably give you 2 options, 1 of which will be a destructive recovery. Using THAT option, your data will go poof.
I recommend that you create an Ultimate boot CD for Windows, "www.ubcd4win.com" , boot to it, and copy your important files to a flash drive.
To boot to an optical disk, you will need, probably, to change the boot order / sequence, in the BIOS, or press something like F2 [ read the HP Invent screen ] notifiying you as to the Key you need to press to access the boot order, without entering the BIOS.
OR, if you are really skilled, remove the HDD from the computer, connect it to another computer, and copy your important files.