If you have intrest in both then you should go for mechanical ngineering because you would have lots of career opportunities either in public sector or it is private sector.If you have future plan for getting settled doing some government ,ME would be the best.If you are in good colleges having good placement rate you can opt for aerospace engineering .If you get placed from the college it is fine but if not you'll have to face problems.So decide it based on the college and your future plans.All the best.