KB2600217,  KB2656351 and KB2633870 are all NET Framework updates.  See THIS from Microsoft about it.  You may have to reinstall or repair the NET Framework itself before you can install those updates.
My system refuses to install these updates but keeps trying everytime I go to shut down my machine (Dimension 5100, Windows 7 SP1, 4Gb RAM).  I have AVG (AV) and Zonealarm (firewall) installed and they are both up-to-date.  I've used the MS helpfiles but am unable to identify the problem (I get an error code - 264 but cannot find anything to help on the MS Knowledgebase). I've carried out a full scan with AVG, and even a pre-boot scan with a Kapersky rescue disk, but everything seems to be OK. However, HijackThis produced a log-file showing some errors (samples below) and I'd be really grateful if anyone can help. Thanks
Windows 7 update - failure - KB2600217, KB2656351 and KB2633870