Hey I could really use some help.

I am running windows XP and have Broadband Internet connected though a Router as this main computer and my laptop are wirelessly connected.

A few days ago, the Internet started playing up. It will stop working for a few minutes, giving me the ‘Page cannot be displayed’ screen and when it does start to work again, it does so at a crawl pace.
It also does this on my laptop when I am on the internet.

It also disconnects any downloading program I have on like Limewire and my Msn and Yahoo messenger, yet the phone line is fine and my Internet service provider shows no sign of my being disconnected.

I read about a similar problem on a forum and tried what they suggested, a DNS flush. That seemed to work for a day, but now it’s worse then ever.

I have also scanned for virus and have found none.

Can anyone help me? Please?