Barcelona I think is the most beautiful port...and it's new. They are developing that area right now. There will be a hotel on the water that is similar to the 'sail' type in Dubai, you can't miss it.
Where are you guys staying, have you booked a hotel yet? Need a recommendation?
Let me know your location and I can give you a few dining options...or you can "PM" me and we can chat more about it. One thing I would do if at all possible, is to grab a ticket for the "HOHO Bus". The HOHO bus will take you to and past all of the wonderful Gaudi sites...but you have to stop at Park Guell, so lovely there! The bus will give you a 3-hour tour and you can take it again and then get off at the places which interest you. If you would like a personal driver, let me know as well and I can give you a referral.
Our "honorary mom" on this thread lives in the Boston area, and she may have some additional advice for you boys as well!
Look forward to hearing from you, AND reading your review of the cruise when you get back!