I have had a wireless network in my house for several months, and although there have been some minor problems, there has been nothing I can't handle.

But recently, it's all gone pear-shaped! My computer can connect to my router, with no problems, and using the Belkin Wireless Monitor, I could see that I was connected to the router, but not to the Internet. MSN Live Messenger also tells me that I have problems with my DNS, saying that it is unable to resolve IP addresses.

My neighbour has kindly allowed me to connect to his router to test the problem, but I can connect fine to his, and he has the same router as me.

Does anyone know what this problem is about, and how I can fix it?

Cheers, nick69topless ;)

Hmmm this sounds like there is an issue connecting to your ISP.
Have you given them a call ?
Do you use an NTL/Telewest connection, as I believe tha they have been having some serious problems recently.