How do i reset a cisco 836 router if i don't know the ip

On the back of the router is a reset button. Press that in for 5-10 seconds. It will reset to factory specs. Once you reset the Valet Hotspot, all of its customized settings (network name, wireless security, etc.) will be erased and the hotspot's IP address will be reverted back to 192.168.1.1, with a default password of admin and no username.

Have you read the quick start and installation guides?
http://www.cisco.com/en/US/products/ps6087/prod_installation_guides_list.html
Yes, the AP should be able to obtain an IP address via DHCP from your
Netopia router.
If this device is used, it may not be setup to aquire things via DHCP,
and you'll probably have to hookup over a console port and do password
recovery.
Cisco's aren't the easiest things to setup, they are more akin to a
box of tools, rather than a single purpose built item, and thus can
do quitealot, but you have to learn how to use the tool first. It will
then let you setup things quite advanced that the single-purpose built
item never imagined, but you have to know how to get there first, not
coast and do the advanced stuff later.

> WAN IP: 44.55.66.777
> ISP Router LAN IP: 111.222.333.174
> Cisco Router WAN IP: 111.222.333.175

Really? Each "octet" must be a value between 0 and 255, inclusive. A value such as '777' is not valid

agree that turn off your modem first before trying to open the router's setup page. By default, there's no username and the password is admin on Cisco 2911

http://www.3anetwork.com/cisco-cisco2911/k9-price_p238.html

For that press RESET button of your router for 10 seconds then it will automatic restart and reset. then connect router to computer lan port with lan cable. then you can access it with default ip addresshttp;//192.168.1.1 or http://192.168.1.2 Type user as 'admin" and password as "admin" or "1234" or "password" or blank then you can see configuration page of router. Then click on wireless->security then note down the password.It's your password to connect wireless.
Let me know if you need further assistance. thanks for using fixYa.

You can also configure it with below method.
Connect your router to computer with ethernet cable then you can access it with following default link. http://192.168.1.1 or http://192.168.0.1 or http://192.168.15.1 or http://192.168.2.1 If you are not able to access it with above ip then check your computers ip address gateway ip is your router ip try with it. Then it ask for user name and password. Type user as "admin" and password as "admin" or "password" or blank. Then you can see configuration page of router. If you are still not able to access router with above ip then you need to RESET it for that press RESET button for 10 seconds it is in back side of router then all settings defaults..Then you can access it with above method. Let me know if you need further assistance. Thanks for using FixYa.

I'm confident that having both routers distributing the same subnet is causing a conflict.
You should change the Cisco router to 192.168.2.1. and let it deliver IP addresses by DHCP.

That should do the trick.

Straight from Cisco:
Password Recovery Procedure for the Cisco 2600 and 2800 Series ...

What's the model number and brand of that router. It's odd if it doesn't have a default IP address. Most routers have default IP. I guess its a Cisco router? If its a Cisco router, it requires a technical person who knows how to configure a Cisco router. Or I'm thinking that it's an Access Point.