IIT Gandhinagar CSE is better
Both the colleges are good. They have outstanding ratings. If you want to choose one you can go for IIT Ropar it has better placements.
You can also compare both the colleges from the given below link
IIT Ropar
http://www.engineering.careers360.com/indian-institute-technology-ropar/reviews
IIT Gandhinagr
http://www.engineering.careers360.com/indian-institute-technology-gandhinagar/reviews
Good Luck!!
College Comparison based on Courses, Placement, Rank, Fee
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile