Hi Katrina,
You'll love the Queen Mary. She's beautiful! I haven't been on the ship in years, but she's a grand old ship and a symbol of my hometown that I have visited throughout my life.
The QM is nestled next to downtown LB where there is a lot to do within walking distance. There is the nearby Pike Shopping and Dining center, with restaurants like PF Chang's, Outback Steakhouse, Gladstones (awesome seafood) and another Japanese and BBQ restaurant that I'm unfamiliar with. next to that is the Aquarium of the Pacific which is a beautiful aquarium. There is a Bubba Gump Shrimp restaurant next to the Aquarium.
If you cross the main street (Ocean Blvd.) to go a little further into Downtown LB, there are a bunch of great bars, restaurants, shops, a Laugh Factory, and a movie theater or two.
If you are leaving the QM to get to DL by opening at 8am on a weekday, you will need to leave early since there will be morning commute traffic. (See my post above about which freeway route would give you access to the carpool lane for quickest access.) I would leave no later than 6:30 am. That will give you time to get there, park in the Mickey & Friends parking structure, take the 3-5 minute tram ride to the Downtown Disney/front park entrance, and wait for the opening ceremonies. If you want to really play it safe and make sure you get a good spot at the gate, leave at 6:00 am and take some coffee and breakfast with you to eat while you're waiting for the opening. (I don't think there's anywhere to buy coffee/food once you park until you're within DL gates after opening, so grab something before you head into the parking structure.) Better to be early and wait, then late and miss something.