Economics

Yes, you can definitely pursue computer science engineering if you had PCM + economics in class 12th. If you wish to pursue a career in computer science engineering, you must apply to one of these colleges for bright future:
IIT's
PEC university of technology, Punjab
Bengal institute of technology, Karnataka
UTM, Shillong

Dear,
There is no comparison of the two fields because both having different market demand and challenges.
If you want to work in a bank or financial institution, opt for MBA after completing BA (Hons) in economics.
Following are the good colleges for pursuing MBA:
1. ISB, Hyderabad
2. Narsee Monjee, Mumbai

Course completion from institutes like Tata Institute of Social Sciences gives best career.

MBA can be pursued only after the completion of graduation. Since, you have economics as a specialisation in BA you could pursue MBA (finance). In case you don't intend to pursue your career in finance then MBA in HR / marketing/operations/etc. could also be explored keeping in mind your interest areas.

They are as follows:
- For economics
(1) Delhi School of Economics, Delhi University
(2) Shri Ram College of Commerce, Delhi University.
- For statistics,
Indian Statistical Institute, Kolkata. They conduct national level test every year. For more details and procedures, visit the respective websites of above colleges. All the best.

Go for USA, that's better.