Hey,
Both BBA and BCA are good fields and cannot be compared as such.
BBA or Bachelor of Business Administration is the study of Management or Business Related Activities while Bachelor of Computer Application which deals with the development of computer applications. After completing BBA,you can work in Corporate Sector as business consultant,finance or sales.
While,after completing the BCA course,you can work as IT Professional ,Network operator etcetra.
Hope this helps.
Good luck.