ATV works with ethernet
The OP stated that without making any changes to his setup, the Apple TV works fine when it's hooked up to his DLINK router with an ethernet cable.
What the OP is trying to do is what Apple calls "Home Sharing" http://support.apple.com/kb/ht4352
This allows his...
Try opening TCP/UDP ports...
As a test, you can reserve the same DHCP IP address for your Apple TV by it's MAC address (see "DHCP Reservation" page 26 in your manual).
Then open the following TCP/UDP Ports (see "Port Forwarding" page 29)
Six network ports are used by Apple TV for...
Try these
(1) Read and try this thread first (make sure there are no spaces in the windows printer share name)
http://social.answers.microsoft.com/Forums/en-US/w7performance/thread/bd920e46-dbeb-4bb2-a38e-8791facd0608
(2) Try Gutenprint on the Mac side...