I have completed my engineering in CS from MNNIT. After talking to my peers in other NITs and IITs I will share with you what I have learnt. You can go to any of the NITs and IIT and if you really want to be good at computer science and really want to study you will have to take the pain of leaning and studying yourself. The profs don’t care and you will hardly learn anything in the lectures that you attend(leaving out a very very very tiny fraction of profs). You will have to do all the learning yourself. You need to consciously make efforts to learn new things and believe me if you are motivated, you have so much opportunity in these colleges. It is my personal opinion that the colleges are good not cause of the profs(some of the profs themselves might be brilliant and if you are lucky you will learn something from them) but because of the students themselves. The students(most of em) who make it in these colleges are either hard working or plain brilliant. You should go to the top colleges where the students are brilliant and there is a conductive environment for learning.
Once in the college you need to also find friends who are willing to learn and will share knowledge. This way you learn better, your friends come together and discuss and this way you learn alot. You can find all sorts of people in colleger and you have to choose who to be with.