Computers & IT (Non-Engg)

In terms of salary just after B.Sc, they are almost equivalent. But in my opinion CS definitely has the edge because of wider range of opportunities and job available. With CS you can also enter into the highly lucrative area of data mining (salaries in crores if you go abroad). You can go for higher education M.Sc PhD. IT graduates also earn a lot (similar to CS) but the problem is many Indian universities don't take IT degree for higher education. Research fields are limited (they are wide of course but I am talking w.r.t. CS). Also thanks to the stigma attached to technical degrees IT B.Tech are more preferred vis. a vis IT B.Sc (same is the case with CS but atleast you can go for M.Tech and make up for that if that causes problem)
As for course work IT is easier. For most part IT and CS courses are similar but CS involves more maths as compared to IT. So if you are a bit uncomfortable with maths, take IT. In the end it's your choice. Hard work and determination can take you to the moon even if you come with an obscure degree like B.Tech in food storage. What I said above was keeping in mind the general trend (the averages). But exceptions are always there.

If you want to design software that interacts with people, then you'll be designing processes that implement that interaction. A process is a sequence of steps that alter some part of the world. You model a process with an algorithm.
The richer the algorithms you can design, the richer the processes you can model in your interaction, and the richer the interaction will be. Ergo, you want to be able to design rich, complex algorithms that express interesting ideas. The language of algorithms in mathematics. For example, suppose you'd like to have some characters whose interactions involve something more than shooting each other.
Let's take an extremely simple interaction: Mary watches Tom do something to Joe. The niceness or nastiness of Tom's action is represented by the variable nice nasty. Mary's affection for Joe is represented by the variable affection [Mary] [Joe].
Can you devise an algorithm that will calculate the degree to which Mary's affection for Tom will be altered by his action toward Joe?
It really is quite trivial, if you can't come up with something good, perhaps you need to bolster your understanding of mathematics.
Hint: we're not talking high-powered math. The first year high school algebra is sufficient.