42 will give you more of the “typical” A&A scenario (Germany starts deep in Russia, Japan is at its historical apex, etc.).
41 will give you a new experience, where the Axis haven’t really started expanding yet, but are tremendously strong compared to the Allies.
If you’re all around the same skill level, play 42. If you have a mix of stronger and poorer players, play 41 with Objectives Off and have the stronger players take the Axis. Axis are stronger in AA50 but harder to play, so the learning curve should be enough to keep the stronger players on their toes.
Good luck with your game!