Anyone know how to disable all the router functions of the Cisco 3825 Cable Modem/Router?

[Obsidian]

My ISP upgraded me to one of these today after they blamed my incorrect overage fees on the old one (piece of junk Motorola). However, this thing appears to be an integrated services type deal instead of just a raw modem.

So I plugged my actual router (an ASUS) into one of the LAN ports, and it works. However, I cannot get the damn thing to stop broadcasting an (completely unsecured) SSID. Disabling the wireless network never sticks; when I hit save changes it just reverts back to Enabled. I'm also concerned that all this thing's DHCP/DNS/QoS settings are going to screw with my actual router.

Is there a way I can get this thing to just act as a modem and nothing more?

Any advice or insight would be greatly appreciated.

Edit: Apparently you have to actually log off for the wireless settings to take effect. I suppose it kept reverting to Enabled because I disabled the Wireless network in the Setup section (why you're able to screw with it in two different places is beyond me), but I'm still concerned that the Cisco's settings may mess with my ASUS's settings.

[Totien]

Replace the firmware with DDWRT or Tomato.