>In order for me to test an application running on a desktop computer from a tablet I need to bring the Home or Private Network Firewall down. Basically when you go to Windows 7 Turn On/Off Firewall you have two networks:
>
>Home or work (private) network
>Public Network
>
>My understanding the the former one (home network) is the LAN - after my internet router. This is the one I shutdown. Do I understand that a hacker would have to hack through the router to get to this network? I thought that since I use WPA-PSK security on my router, hacking is unlikely. Am I right?

I wouldn't take the firewall down completely, just set up inbound rules for the necessary services:

http://stackoverflow.com/questions/3244158/how-do-i-expose-local-iis-to-other-pcs-on-windows-7

If you do drop your firewall yes, you still have protection from the public Internet via your router's firewall, and from WiFi hacking via WPA (preferably WPA2) and a strong password - at least 20 characters long is recommended these days. Turn the firewall back on when you're finished testing.