Internet doesnt work!

I connect to the net properly but no page loads. It shows page cannot be displayed. Even my email app i.e. msn cannot connect. My modem is fine even my phone line.
When i goto control panel -> network connections -> local area connections, it displays as connected.

What could be the problem?
I just re-installed my whole computer and everything was working fine for a while and then the internet just stopped.

One of my freinds was actually using the computer trying to install a sound-card so he might have messed with some of the settings. I have no ideaa.