BCA

The B.Sc (CS) contains all the concepts, thesis and fundamentals of computer that one needs to know before entering into a computer field. Subjects like mathematics (Boolean algebra, equation solving, graphs), microprocessor architecture, history of computers and generations of computers, etc. are part of this course. But B.Sc won't provide the technical knowledge on any particular technology like Java, Oracle etc. They would just touch technological products like MS-Office and Java, but never in detail. Thus B.Sc alone may not be sufficient degree to get good jobs in the computer industry that requires specialization in some or the other technology. Though data entry jobs and other such jobs would be available. B.Sc has general syllabus and is not said to be a specialized course. In B.Sc theoretical aspects are going to be covered.
BCA on the other hand has more technical knowledge with the inclusion of programming languages like Java, C, DS, C+, Databases (MySQL, Oracle), etc. Thus one may get a decent job in a company even directly after getting BCA degree.

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 like M.Sc or 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.