What are the depths for both dives? Will it be the only dive for the day? It will boil down to a few things. 1) what is your comfort level, 2) what type of dive have you experienced most often 3) what are you more interested in seeing
Drift dives are a ton of fun because you flow with the drift and the boat will pick you up when you surface. A wall drift dive could be exciting because there will likely be some nice sea life to view, from various corals to eels and fish (Also depends on your climate, is this an ocean wall or a river?)
Wreck dives can always be a lot of fun too with lots of sea life as well and a plane does sound like it could be a neat wreck dive. I think it is really going to be your preference on what you want to see more, and what you are most comfortable with.
Going back to your actual questions: What would I do? I've done a few drift dives (not along a wall) and it was great, but I haven't done a lot of wreck dives so having a chance to see a plane wreck sounds exciting to me, and i also like sharks and they are often found around wrecks, so if it increases my chance to see one, then it sounds good to me! (So assuming the wreck was with in my depth limits for my advanced open water cert, i'd probably want to do that).
