I have allowed the update manager to install a 200 Mib of updates, and I think that these update run my graphics driver into a problem. So, I need a way to remove the updates that have been installed since 30th of may 12 for example (or any other date). If I have to remove them manually (in the case of uninstalling them one by one), you are kindly requested to give me the instructions of how to do that.
You can open Ubuntu Software Center, and click on history
Once you do that, click on updates, and that will show you all the updates that are installed on your system. Once you find out the updates that you need removed, you need to do that manually.