Hey
BCA and BBA both are three years full time  Undergraduation course divided into six semesters.
Difference between the two degrees:-
1. BBA is a management course while BCA is a technical course in the field of computers.
2. The concepts of BCA are easier for students having done their 10+2 in science subjects while for others, BBA is Better.
3. Both BBA and BCaLA have diffrent diffrent careers.

Scope of BBA
1. Accounting
2. Business law and ethics
3. Economics
4. Financial management
5. Cost and Management accounting
6. Marketing
7. Operations Management

Scope of BBA:-
1. Computer graphics
2. Programming languages
3. Database management
4. System analysis
5. Animations

Analysis
It is very unfair to make a straight comment on which one is best or which one is better. Both the feilds have their own importance and Necissities.
First of all, you should find at what you have talent or at what you're excellent between the two. Also your interest matters.
They both have huge scope. After BCA and Bba you can do MCA and BBA as a post graduation course.