Disabling of such things is usually not an option (as manufacturers implement it). But look in running apps. I think I saw something like "update service" or similar. If you freeze this one, the "app" or "setting" shouldn't be able to check for new updates.
Other than this, there is an option to just get notification of new updates and decide for yourself whether or not you want to download the update. This can be found under the last item in settings "about your tablet">"software update". Under the last item here you find an OS and an apps section.
Hope I could help or at least give some useful hints.