Can connect to router but internet has stopped working

It seems that many people have been having the same problem but I couldn't find any solutions. I use a router to connect to the internet and everything has always been smooth up till today.

The problem is this - my MBP sees the router and connects to it with a very strong signal, however I no longer get a valid IP address (I get 169.254.213.18) and cannot connect to the internet or access my router's homepage.

I run latest version of Tiger with all the latest updates, the last Airport update was 27th March, I could connect to the internet fine after installing that update. The problem only started today. Have not installed any new software recently or changed any settings on my mac or my router, just woke up and found that I can no longer access the internet.

Things I have tried which haven't solved the problem:
- Reset my router and all its settings
- Rebooted my MBP several times
- Tried different browsers
- Unplugged and replugged all wires connecting the DSL modem and router
- Tried a direct ethernet cable to my router, internet works, so I guess the problem isn't the router?

Would appreciate all the help. Thanks in advance.

 

Using DHCP.

Used basic WEP security before the problem occurred but it's currently open since I've reset my router several times.

 

Haha nope not complicated at all, I actually already tried that a few times, just tried it again (changing to BootP and Manually then back to DHCP). Still same problem. Thanks though!