The flight scheduled to depart @ 23:10 was delayed by almost 2 hours. We could see so many families with kids stranded. Worst part was that there was no Air India representative at the boarding counter till 00:15 AM to answer the queries of frustrated passengers . To make things more worse, once we boarded the flight, the air condition of the aircraft wasn't working which was even acknowledged by the captain. Toddlers were having a tough time in that suffocation . To make things more bad for passengers who were hungry due to delay of 2 hours in midnight, what was served to all was Half piece of sandwich & one frooti. This was very annoying and disturbing as after 2 hours of delay in midnight, the least the airline could have done was to arrange some additional food for stranded families . Finally the passengers could come out of the aircraft @ 2:25 AM instead of 00:15 AM.