Hello Saurabh

If you are in General Category then PSU's chances are nil. If your AIR would have been less than 350 then the chances would have been there.

Coming to IIT's, yes you can get into top IIT's except Bombay, Delhi, or even KGP and Madras. Other than these IIT's you can get Roorkee, Guwahati or may be Kanpur. Apply for all the above and hope for the best.