Hmmm. If it redirects you all the way back to the home page after clicking SAVE, something else nasty is going on.
On mine, when I click SAVE, I get a pop-up that says "Modifying your network settings can make the device unmanageable..." yada yada yada.
Then when I click "Continue," the settings are saved and it stays at the same page (and the Save button disappears.)
Last ditch effort: Try doing the "Soft" reset. When the device is fully booted up, press and hold the RESET button for > 4 seconds.
This reconfigures the network (and passwords) back to factory default configuration.
This essentially rebuilds all the network config files (or at least, it should.)
If THAT still doesn't work, get your data off the drive and do a "Quick Factory Restore."