Hi
I have to vote on the side of it's not the hard drive.
If it was you would be a lot more likely to get an indication to enter the bios, when you turn the computer on, generated by the mother board and not have any screens relating to Windows install.
It is possible I suppose that the virus or whatever it is did corrupt the install files in the recovery partition.
What does happen when you turn the computer off, hold 0, and turn it back on?
Does it show anything on the screen?
It would be interesting to see what happens if you did the Ubuntu thing on another computer, boot from the disk, and see if you can see what's on the hard drive, or if it's unreadable from Linux too.
Unfortunately getting a Windows 8 ISO file isn't as easy as it was for previous versions.
I don't know if there has been some breakthrough in that area.
Putting in a new hard drive would solve your problem, but you would lose all your stuff, and you would have to get Windows install media from somewhere.
Only slightly related, but a friend who runs a large school system had his computers all hijacked and had to pay a ransom to get his data freed up just in the last year, he had no option because they had to have the data.
He found other local school systems who had the same thing happen, now one knows where the perpetrator is doing this from.
They are a lot more stringent about backing everything up now, if it happens again they will just wipe the computers.
Mike
