OK, here's Plan A:
Go to the Programs and Features, on the left is an option to "View installed updates" - select that.
Find the entry for KB2656351 and select Uninstall from the top.
When it has finished, reboot your computer.
When it has re-booted, go to windows update and it should be ready to download. I would de-select any other updates, so that it only does that one.
That should sort it. If not we'll try Plan B with the Removal tool link.
I'll be working until late tonight (at least 11pm), will check in to see how it went.
Good luck!