No, there's no elevator button. And don't bother asking for it by that name either. No one in the hotel will know what you're talking about.
You might ask for it by its current official name, the Presidential Suite, but likely few people will know what place you are talking about. If you must ask, mention the Marina Suite, and almost everyone working at the Disneyland Hotel will know exactly where to direct you.
But the elevator button you push is 11. In the Marina Tower (no, that's not what it's called now) - which is the "main" tower with the front desk and check-in counter. At Floor 11, turn right out of the elevator and proceed to the doorway on your right with steps leading up to it. You're arrived.
In more ways than one.
