I need to find the file that contains the Windows version. Windows will not boot, so I need to run a repair. I cannot do so without knowing the version that is installed.

To run the Repair option you'd need the original Windows CD, if you have that then you know what version you have.
So you know for sure it's not Windows 7?

To run the Repair option you'd need the original Windows CD, if you have that then you know what version you have.
So you know for sure it's not Windows 7?

I am running IT for a company. I have dozens of discs. Not sure which is for which machine.

Often there is a sticker on the machine with the Windows key. That usually has the OS version on it.

It says Windows 7, but it doesn't specify Professional or Home. I have discs for both.

Pop in the disc, the worst that can happen is that you get a message saying something about the wrong version.

A company should not be using Home so try Pro.