First of all, throw away the install CD because the setup software is junk. Use the Netgear web interface. Most routers these days has some sort of web interface. More details at the bottom....
Second of all, you already have a wireless router. The 2Wire 1800HG is a... well, wireless router. There's not much of a reason for you to add another wireless router and if you do, you're in for a world of problems unless you're familiar with how routers, wireless and IPs work.
If you insist on using your Netgear as a wireless router, then you'll need to disable your 2Wire's routing capabilities (Turn of DHCP and turn off wireless) and (hopefully) use it as just a DSL modem bridge. 2Wire should provide this information on their website or via phone. You should be able to perform these functions via the web interface, which is probably 192.168.1.1 or 192.168.0.1 or 192.168.2.1... in that order of likeliness.
The other choice is adding your Netgear as a wireless access point and allowing your 2Wire to do all the routing, but I don't see much purpose in this.
Netgear has documentation on how to set it up as an access point only.
http://kbserver.netgear.com/kb_web_files/n101496.asp
To use the web interface for your Netgear router, connect your computer with a cable to the router and wait a few seconds. Open whatever Internet browser you like to use, type in the address
192.168.0.1 and press enter. It shoud prompt you for a user name and password. The default user/pass for most netgear products is
admin and
password.
If it doesn't bring up anything, reset the router by holding down the little reset button in the back with a pen or paper clip etc.. Try it again and it should work. Keep in mind this will reset all/any settings you may have had back to factory defaults.
If portions of this don't make sense, please do ask me to elaborate. I'm just being brief because I'm short on time.
