Update -
Just called AMEX using the "International Collect" number on the back of my card (336-393-1111), instead of the 1800 number. Went through the usual phone tree...
Got a guy in SALT LAKE CITY! (I don't know if this always happens, but it sure was a breath of fresh air!)
He solved all of my issues in about a minute. No Select and Pay Later feature for me! He also said that I would be receiving a confirmation letter that I opted out of this feature. Thanks everybody!