Dear Ravi,
1. Indian Airlines will stick with timings but you never know about flight timings. Even Singapore airlines cann't assure u about them. So they are as reliable as any other airlines. It is Indian not Indian Airlines !!!
2. Deccan, good if u r travelling without luggauge. Bad reputation for services but again budget airlines like easyjet of UK and Ryan air of Europe are having bad reputation. People use them for economical reasons. Not suitable to fly as a connecting flight along with international flight.
3. Expedia is very reliable. I have used that for booking hotels in Europe and Arab and they are excellent. I always book flights with them. Little expensibe but much better than thieves like
www.southalltravel.co.uk (owned and run by our own Indians from UK).
4. Air India flies from Delhi to Amritsar at around 3 am. So please check with them. If u land in Delhi at around 11 pm it should be best suited for you or your kids.
Hope this will help.
Guru Fateh