If it boots to a C
> prompt then at least DOS is running. In which case it is possible to download a file transfer program via laplink type serial cable. Finding the software can be the awkward bit.
TranXit is one that I have however I think it needs at least Win3.1. Not sure if it will operate DOS only. Although on second thoughts, it uses DOS alone to take control of the serial port & download itself onto the target PC.
Alternatively you could get a book with the DOS commands to do the downloads manually. You would still need the serial cable though.