Hello, Noreen!
You are going to love your stay at Disney's Port Orleans-Riverside! My son and I just returned from that resort two weeks ago; he was immediately so impressed that, as we walked through the resort after our 9:30 p.m. arrival, he spontaneously shouted "MOM! This is beautiful! I can't believe we're staying here!" (This after 30 prior stays at other resorts. It's that lovely!)
Regarding your dinner at Boma, at Disney's Animal Kingdom Lodge, I suggest that you take a Resort Bus to Disney's Animal Kingdom Park, then hop onto an Animal Kingdom Lodge Resort Bus. The trip from AK to the Lodge is just a few minutes, so this is an easy way to get from one resort to the other. If your dinner is very late and there are no longer buses running to AK, just hop onto a Resort Bus to another theme park, then take a Resort Bus to POR. Some folks swear by the "take the first park bus that arrives" method, while others head to the park which is either closest to their final destination or is on the way to their resort (which, in this case, would be Disney's Hollywood Studios or Epcot.) Take a look at this
Resort Map for a better idea of how this works.
Guests at AKL are welcome to observe the animals on the savannah as well as explore all of the wonderful nooks and cozy pockets of art, activities and Cast Member interaction throughout the resort. Make a night of it; you'll be so glad that you did!
Have a great trip! Be sure to send more questions as you think of them; I'd love to help!