Brandie, welcome back! I'm happy to see you're still considering a cruise on the Dream!
The good news is that not only can you request to be on Deck five, you can choose exactly which stateroom you'd like based on what is available. Take a look at the
Dream's Deck Plans. (Click on Deck Plan and then choose Deck five.) You can hover your mouse over each stateroom to find out the category and stateroom number. When you find an area of Deck five that you'd like, simply let your reservation agent at Disney Cruise Line, or your travel agent, know and if it's available, it's all yours!
Deck five on the Dream is home to the Youth Clubs which take up a significant amount of that deck, as well as the Buena Vista Theatre. Because of this, the mid section of this deck only has a hallway on one side of the ship. However, you can certainly walk from Forward to Aft on Deck five, making a few turns in the process.
I hope this helps you plan your cruise, Brandie! Please let me know if you have any other questions as you're researching Disney Cruise Line!