Sir,
This is really bad that your computer crashed and you lost access to your files. This is truly a loss for you, but in a way for the many people that have watched over the years your building of these creative and interesting model engines. Hence, I don’t want to tell you what to do but suggest only some ideas from my experience.
Please do not discard the currently installed hard drive. It is highly likely the files are not corrupted but that addresses to access these files have been scrambled so that Windows cannot find the files. A PC-computer guru could apply his talent and software to gain access to your files on your corrupted hard drive. These people exist but they’re little hard to find in my experience. I called around and found such a guy in the IT department to a local university. He made a house call and got me out of a big pickle . . . he recovered my files! You could avoid the cost of a house call if you removed the hard drive yourself and delivered it to the techer (Remove AC plug form computer power supply and wait until LED on power supply is off; it takes a while for capacitor to fully discharge. Remove two connectors form rear of hard drive and the mounting screws and you’re off.).
As an aside, you might consider replacing your current disc-hard drive with a solid state drive (SSD). The capacity of these units has greatly increased and the cost has come way down, e.g., Samsung SSDs. Such a unit in my seven-year-old computer made it like a new machine when the operating system and application softwares where installed on this drive.