M.Tech

Yes IITR is one of the best colleges for computer science education especially masters. M.Tech from IITR will fetch you a better placement in the future.

MBA is more demanded one. Nowadays many of the major MNC's look for B.Tech + MBA graduate rather than M.Tech. They want students with technical and managerial skills.

You can join the institute by taking a competitive exam called GATE which on clearing will allow you to study in the IITs, according to your rank.

Hello Sunny,
After having done B.Tech in CASE, why you want to change branch? Universities abroad are quite liberal in giving choice of subjects. But to do MS in Aeronautical engineering seems I little far fetched. But you may make an attempt.

Hello Manash,
For doing ME or M.Tech, you need to have done graduation in engineering. You have not done this, hence I am afraid you are not eligible for admission to M.Tech in IIT.

Hello Nishant,
First of all, I would recommend you to think about this situation again as this would make your previous qualifications (B.Tech and M.Tech) of no use. You can always complete your M.Tech and do the BA course whenever you're free. But withdrawing your M.Tech course in between and going for BA will raise many questions. Ultimately, it's your decision and you can opt for BA with the same university if they have the particular course.
Best of luck for your future.