Ubuntu is a great OS that let its users know which all updates are available, by itself making it easier for them. However there is no guarantee that the updates will be installed with the fastest server.
So here is a trick for the Ubuntu users with which they can ensure that the server selected for installing the updates is the fastest one therefore taking least time to update.
1. Go to System -> Administration -> Software Sources.
2. Under the option reading Downloadable from the Internet choose Other.
3. Then select your country or the one nearest.
4. Now click on the Select Best Server button and wait for it to finish.
5. When you are ready, click on the Choose Server button and close the main window.
6. Now you will be prompted to reload the server but click on the close button instead.
7. Click on the reload button at Applications -> Add/Remove… (clicking the reload button at previous step might freeze up the system).
The updates should install at a faster rate now.