I presume that you mean "from a web site" that the web site is hosted somewhere out on the greater internet.... The problem that you are encountering is probably related to NAT (Network address translation). The "In" side of a router, is typically a "private network" there are pre-assigned number groups for these - a common one is in the 192.168.x.x range. Problem is that the "outside" of your Netopia router will be dependent on your ISP< and unless you are paying them extra for a static IP address, is likely to change every time you reboot - or sometimes they bump them every 24 hours. So, first thing is get a dynamic DNS Entry - www.dyndns.org is one supplier - I think you can get one address for free from them, pay for more.. YOu set up something like CMVideo.dynsdns.org on their site, and set up dyndns support in the netopia router... Then you want to open the specific port on your router, to go to the internal IP Address of your camera. (YOu mention Multiple Cameras - depends on the Camera you may have to go for multiple dyndns (one for each...) ).

I am a little confused/concerned about the second router "tier" - if you have the Belkin configure as an Access Point only, all good, if you are trying to run it as a router behind a router, it will probably never work - double nat-ting" is a no no with most consumer Routers. Simple solution is to tap from Netopia lan side to Belkin Lan side (rather than Belkin Wan Side)