I am a bit puzzled and would like some help with this query please. I have been using the update manager in Ubuntu 11.10 and to date there have not been too many important updates since I upgraded to 11.10 and it has been working fine. Today however when I checked for updates it has come back with 203 updates. 3 of them important security updates and 200 appear to be updates for programs which I thought had been removed during the upgrade process. (not sure why I think that, except some games were listed which I thought had gone). When I try to install the updates it produces an error message explaining that there are unmet dependencies and I should disable all third party repositories. I have tried this, disabling all the other software sources but to no avail. I ran 'sudo apt-get check' in a terminal and have been advised to run 'apt-get -f install' to correct unmet dependencies.
I really don't know that much about these things and need to know if this is advisable. I really don't want to break my system and have to start over. can anyone offer some help please. Apologies for the convoluted way of explaining things.