From my knowledge Google Chrome actually uses the proxy settings from Ubuntu, so does Firefox. Check that you don't have any proxysettings set in Ubuntu:
- Go to the Network application
- Click on Networkproxy
- Set method to none
- Press Apply settings to the whole system
Not sure if the names are correct, but it should not be hard to find.
Another easy way to debug this is to use another IP from the tor network, if the IP revealed to websites changes then you know you are on the Tor network.
You can find sites to check your IP with by using google or by using this site: http://whatismyipaddress.com/
If you are in fact not using a proxy then it might just be an GeoIP error.