Two methods, both use qemu.exe:

Method 1: Initiate a dialup connection under Windows, then use qemu.exe
to load your iso file or cdrom: "qemu -cdrom *.iso"

Method 2. Do not initiate a dialup connection under Windows, then use
qemu.exe with "qemu -cdrom *.iso -serial COM3". COM3 is the modem port
in Windows using a modern Conexant chip. Then, run pppsetup under Linux,
manually selecting /dev/ttyS0 as your modem device. If you have ppp
installed on your Linux, you ought to hear the modem noise as it starts
up and get all the modem connecting messages for pppd.