If you are unable to accomplish the task yourself after trying, I say it is fair to push the F/A call button for assistance. Excluded tasks: Any form of heavy weight lifting notably putting suitcases in or removing them from overhead bins.

For drinks I am not sure of the answer because it seems safer for an F/A to carry a drink down the aisle to a passenger's seat rather than the passenger himself. This should be a poll question where the airlines answer the poll.

F/A's should not be rude even if passengers are not abiding by policy.