If a ping successfully gets out but web traffic does not, try pinging google.com then navigate using the IP address instead of the name. (type the ip address into the web browser)
If you are able to get to google using the ip address then you most likely have a proxy enabled (lots of viruses do this), or dns filtering on your internet connection. Contact your companies IT department either way and they should have a quick fix for you.
Additionally, if you upgraded your windows 7 installation yourself, then your IT department will most likely have to delete your computer object from AD and recreate it as your machine password no longer matches the DC's password. (The user password in only part of domain authentication)