I'm assuming that you mean that some of the translate or rotate channels are unable to be changed? You do this in the channel box, right click on them and select "lock and hide selected". This will lock those channels (can't change them) and hide them from the channel box so they don't clutter things up.

If you're talking about something different, post a screenshot and indicate the area that you're wondering about.

Edit: If you want to get deeper into that, there is a dedicated window in maya. Windows > General Editors > Channel Control (I think it's called something like that). This will display all the channels that are locked, un-locked, hidden, visible, keyable and non-keyable. You can change things here, e.g. getting a hidden channel visible in the channel box again. Hope that helps.