How to use machine name of iOS devices on network?
I use a Time Capsule as my Wifi router, and all my devices are registered in the domain (e.g. "lan") once a device has a lease and each device receives the "lan" domain as the search domain as part of the DHCP config.

Pinging 192.168.0.xxx, iPhone4.lan, just iPhone gets me to my device.

If you can ping the devices by IP address and not by name, then the answer lies more in your home network than in the devices themselves, and how the DHCP server registers device names once a DHCP lease has been obtained.

If your Windows machine has a static IP address, then its quite possible all you need to do is add the Wifi Lan name into the DNS Search config on the Windows PC, but more information is needed on how you are configured.