Well it totally depends on your interest.
If your BTech degree is on computers and you are very much interested on higher education MCA is not the right thing to do. It will not add any value to your profile and your career.
Well it totally depends on your interest.which field you like to work:

MBA:

Its for those candidates who like to interact with people and want to work in business sector.If you have interest in the management sector then this is a best course for you .

After completion of this course you can work in any of the following sectors :

Industrial organisation

Financial sectors

Education institutions

Exports companies

Business organisation

Insurance companies

Logistics companies

MCA ::

The top level IT companies and consultancy firms like TCS, Wipro, IBM, Oracle etc offers great job opportunities to a candidate with an MCA degree.

You have opportunity to work in these area

Sr. Software Engineer / Developer / Programmer
Software Engineer
Software Engineer / Developer / Programmer
Project Leader
Project Manager, Information Technology (IT)
Test / Quality Assurance (QA) Engineer (Computer Software)
Software Developer, Web Applications