The port is in a fine area of town, but yes, you will need to take a cab to go almost anywhere.
We took a cab to see the cliff divers.
Then we took a cab from there to hardrock and planet hollywood (they are side by side), then we took another cab from there to Carlos and Charlies for lunch (wonderful), and then a cab from there back to the port.
Just stay away from the guys in the blue shirts when you get off the ship, they want to lead you to the flea market..which is horrible and way over priced. The best souveniers are right in the little building you go through to get into acapulco. There is also a senor frogs tshirt shop (no restuarant attached) that has great tshirt bargains. The senor frogs, if you want to go is on the far end of the bay, quite beautiful I guess for pictures.