Many of the old dot matrix printers are Epson-compatible, and as such, you could send the appropriate escape sequence to the printer to change modes, pitch, character size, etc. For example, see
this page. A search on Google or the like should turn up a wealth of resources, and if the Epson codes don't work, you can search for the ones for your particular model of printer.
Is there any reason you can't just print from Windows, using a Windows-based program? Are you trying to support a piece of legacy software, unable to find Windows drivers, or what?