jasepl: You should be fine with the 7:40 flight

It's giving you 1 hour 10 minutes in ZRH, and your past experience must indeed have been very unlucky - I've rarely experienced queues at immigration, and certainly never more than 5 minutes, in ZRH. 1 hour 10 minutes will give you plenty of time. Of course, if you absolutely can't miss your flight for an appointment in Bombay, then book the earlier connection, but as you're with a Schengen Visa anyway (which means, LX would be able to book you onto another connection or place you in a hotel) I would take the 7:40 flight, and have no hurry to the airport at Geneva in the early morning.