I'm guessing here you're talking about PAC Display (vs. groov). A couple of thoughts come to mind here, but first a question on what you mean by "disable" for those buttons. If they're not EVER used, you could just delete them. If they sometimes don't apply, you could use the "Control Engine Driven Attributes" option for Visibility/Blink to make the buttons invisible when appropriate.
I'm not a GUI expert, but I'd resist doing some kind of "gray out" thing, since that can be frustrating for a user who can see but not use a button (especially if they don't know why). I've experienced that myself when I can see the option I want, but it's "disabled" and the help doesn't tell me why.
Can you tell us a little more about your situation there, and why/when you'd want those buttons to appear or not?