Uh, I do believe that FAA rules do in fact require you to have your seatbelt fastened. Pamda may be able to confirm this as a former flight attendant. I do know that if you refuse the plane will not leave the gate and you will be removed and in these times in all probablility be charged with a felony for interfering with a flight crew!
As for the lifeboat drill, yes it is a fact that it is required by law to hold them and technically I do believe that addendance is mandantory.
Jim