To disable updates, navigate toHKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\JavaSoft\Java Update\Policy\
The official fix, per Sun, would be to create a new DWORD value called EnableAutoUpdateCheck, and set it to 0. Unfortunately though, it didn’t work, perhaps because the update had already been checked for, and was in queue just wanting to be installed.
Changing the key EnableJavaUpdate to 0 worked without needing to install updates, and stopped prompting non-admin users from installing updates.
An alternative method would be to stop the update utility from running by deleting the keyHKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Run\SunJavaUpdateSched