I have Ubuntu 12.04 with Unity (to be precise I've upgraded a year ago) 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?