From your posting it looks like you wish to disable SSL 3.0 on a IIS webserver. If that is the case you are totally right with your links and the following registry key should disable it:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\Schannel\Protocols\SSL 3.0\Server]
"Enabled"=dword:00000000
Keep noted this will disable only SSL 3.0 for server components. If you wish to disable as well SSL 3.0 for the build in server IE browser you need to use:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\Schannel\Protocols\SSL 3.0\Client]
“DisabledByDefault”=dword:00000001
After you disabled SSL 3.0 for the server you need to restart the whole Windows 2012 Server after that. Additional keep noted that if you use some 3rd party Software on the Windows 2012 server which do not use the MS Schannel implementation (e.g. an Apache server) then you couldn´t control SSL 3.0 via the Microsoft registry key. So if this isn´t working for you it might be that the HTTPS webservice which still allows you to use via SSL 3.0 is not an IIS.
By the way a better option to check if SSL 3.0 is disabled (instead of using a browser) is using nMAP. You can find here a small tutorial how to use nMAP.