Do you have a third party firewall, like Norton, Zone Alarm or other installed?
Try turning off your Windows or third party firewall to test connection in IE and Firefox.
If it worked with your firewall off you need to allow those applications to connect in the firewall settings.
Chrome install shouldn't have affected your internet connection in other browsers.
I installed Chrome and have IE7, FF3 and Opera installed on Vista without any issues.
Also you could restore to when they were working. System Restore: frequently asked questions - Windows Vista Help