Hello Vineet, 

IIITM Gwalior is a renowned college for it's dual degree course in Information Technology.

On the other hand, the ranking of IIIT Lucknow is also very good.

If you are interested in doing M.Tech. too after B.Tech. then you must opt for Dual degree course but as there is not much need for PG course if you directly want to get placed and getting a job is your final aim. If so, then there is no need for you to pursue dual degree course instead you must focus on completing B. Tech..

So choice is ultimately yours. But I hope this answer might help you decide depending upon your own choices.