A lot of opportunities are there for B. Sc computer science students.
You can apply for the government exams too.

Private jobs:
It can be broadly classified into two fields.
1.Software
2.Hardware and Networking

In Software field the the list of famous courses are as follows:
JAVA
DOT NET
C PROGRAMMING(THIS IS BASIC PROGRAMMING LANGUAGE, EVERYONE SHOULD KNOW)
C++
c# PROGRAMMING
ASP DOT NET
JAVA SCRIPT
PHP

HARDWARE AND NETWORKING FIELD:
CISCO CETRTIFICATIONS
CCNA
CCNP
CCIE

MICROSOFT CERTIFICATIONS
MCSA
MCSE
MCP
MCITP

Apart form these data base courses like:
oracle
sql server 2008

Another booming field is
CLOUD COMPUTING

All above courses are very famous, if you learn it properly surely you will get job in MNC's.

They can get job in the following companies:
HCL
COGNIZANT
ACCENTURE
3I INFOTECH
INFOSYS
WIPRO

WIPRO never accepts a graduate with less than 60%.

In other ways a lot of opportunities are available in the government sectors too.

Government Jobs:
SSC CGL
UPSC Civil Services

The selection of best books will play a great role in deciding your rank.
If you have a good collection of books then your preparation will be better.
At the same time your hard work to finish the syllabus of optional subjects will play a great role in deciding your rank in the mains.

In order to have expert level knowledge of General studies the recommended books are:
General Studies Manual -McGraw Hill Publication
Arihant Publication
Upkar Publication
UPSC Portal books
Pratiyogita Darpan study material , Civil Services Chronicle, Competition wizard for articles on important issues.
Most common optional:
Public administration
1.Fadia and Fadia
2. Laxmikant from McGraw Hill Publication
3.UPSC Portal study material