New To Wireless...need help

Having never touched a wireless network before i thought it would be a piece of piss to set up...

I bought a D-Link 300T adsl ethernet modem, which out of the box worked fine in my computer instantly, however reading numerous reviews i was recommended to upgrade the firmware in order to connect to a wireless router (the one i bought of these was a Belkin F5D6231-4). I tried it without but the router kept saying ERROR in connecting, so i updated the Modem firmware, low and behold even without the router i can no longer connect to the net with the modem (I'm currently on my old modem which is USB only). However, now when i plug in the modem to the router, i can get the router to connect to the net supposedly (at least the router is reading internet connected...even when i unplug the phone line it reads internet connected

Can anyone help? what am i doing wrong? are both pieces of equipment faulty or have i gone about setting it up wrong? the Belkin piece only allows for PPPoE or Dynamic, i normally use PPPoA but using dynamic would be the only way to make it work now... HELP please