There r many good government organisations that give good opportunities to computer science people to learn, explore yourself and give your contributions towards nation.. First important thing is job satisfaction that will come if u r satisfied with your work as well as u r got enough salary package for this so that u can live Ur life peacefully.
Some of companies are ISRO, BARC, NPCIL, etc. Maharatna companies like ntpc, cil.
Apart from these BEL,HAL, AAI, etc are there who give job Opportunities to computer science people but thier pay scale is less as compared to Maharatna company..
So, All d best for your Future..