Those are uninstallers for the various patches from Microsoft. The "famous" patch thursday... They are there in case some of those parches may be causing some problem and need to be removed. A patch may not get installed corectly for instance, or may be causing a conflict with some peculiar application.
If the patches works correctly, then after around a month, you can safely delete them.
Most peoples could even delete them the next day, but I don't recomend that.
Also, many patches replace the same file on different occasions. Uninstalling an older patch can realy mess things up if any newer patch changed the same file(s).
In a way, removing older patch uninstalls can prevent some problems.
Electro, September 2011
