First cruise-congratulations! It will be over before you know it, and the time in between embarking and debating will be filled with new experiences. Explore the ship, read the navigators, attend what you think you would enjoy.
We did not do bingo our first cruise, but many people love it, so our second cruise we played bingo. While fun, I'm not sure it would be something I would seek out to do specifically. Just an example of try out an activity, and you'll know for next time. After two cruises, we've only ever watched one movie in the theater on board, but I would totally do this again as it was a fun atmosphere and we watched a recently released movie in a packed house. Check out the kids clubs during posted open houses - you may find yourself being unexpectedly silly as you admire/enjoy the fun atmosphere (even if you don't have kids). Sometimes they hold adult events in the kids clubs later at night - and I've always heard good things, but we've not done this yet/not sure it is always offered -we were too tired the night it was offered on the Magic.
Once on board, I'm sure you'll start to find what appeals to both of you. I do, however, concur that the treats in Cove Cafe (adults only) are worth checking out on a daily basis. Their coffee drinks were all very good, too.