First, and most obvious, is that every menu ("Push one for x, push two for y") should begin by revealing the number of choices on that menu. I know some systems do this already, but it's certainly very rare, and doesn't seem as if it would be very difficult to implement. How 'bout "Please choose from the following four options."

Next, make the choices sequentially numbered. Don't give me 1, 2, 4, 6, and the pound sign. Number them one through five.

Make top-level menu choices based on the type of user. Just as links on a web page shouldn't be designed around the organization of the company, the main voice menu shouldn't be broken down according to divisions within the company. Bad: "Press one for sales, two for technical support, or 9 to repeat this menu." Good: "Press one if you want to find out more about our products before purchasing, press two if you already own one of our products and need help with it."

It's been mentioned a million times, but it bears repeating: Make An Actual Human one of the choices. I suggest standardizing on 0 reaching the operator, but I have the suspicion that the people who design these systems are already so user hostile that asking for anything like standards would be anathema to them.

This last idea I'm not sure how to implement, but let me try to explain. (Feel free to offer suggestions.) Have a "soft selection" option. Perhaps pushing pound and then the number of the menu option would indicate "Maybe that's the one I want." Then, when the user reaches the end of the menu, the system would automatically repeat the menu, but only listing those options that had been soft-selected. Instead of the 9 top-level choices, the caller knows they either want 4 or 6, and those two menu descriptions are repeated to them.

Regardless, the sorry state of voice mail makes the web seem downright easy, and that's amazing if you consider that various forms of voice mail have been around for 15 years.