I have Ubuntu 12.04 with Unity and for the last 3 months or so it's been offering me a partial upgrade. The only things that cannot be upgraded are the kernel and dropbox. I'm still on the 3.2.0-37-generic-pae kernel. On my another machine (12.04 with MATE) I had the same problem but it disappeared on its own. What should I do to go on with normal life?
apt-get update && sudo apt-get dist-upgrade in a terminal
NOTE: "dist-upgrade" does NOT upgrade the system to a new version of Ubuntu.
See man apt-get for details
dist-upgrade in addition to performing the function of upgrade, also intelligently handles changing dependencies with new versions of packages; apt-get has a "smart" conflict resolution system, and it will attempt to upgrade the most important packages at the expense of less important ones if necessary. The dist-upgrade command may therefore remove some packages. The /etc/apt/sources.list file contains a list of locations from which to retrieve desired package files. See also apt_preferences(5) for a mechanism for overriding the general settings for individual packages.