As other people have said, it depends on the winds and which way you end up approaching from. It's not guaranteed you'll see anything at all. But on my last trip to WDW in August, I was sitting on the left side of the plane and spotted Universal Studios out my window. At pretty much the same time, I heard people on the right saying they saw parts of Disney World. This was about 20 minutes before the plane landed, as we ended up having to loop around, so I have no idea which direction we came in to MCO from (we were flying from Milwaukee, btw).
Basically, my point here is that there's no way to know ahead of time. But from looking at a map, I do think that if you're coming from the north, the right side is probably the better bet. So I'd tell you to pick that side, but don't count on or expect to necessarily see anything.