The domestic terminal has a Oberoi restaurant that you could use to sit around. Otherwise its a basic mix of shops and airline/car rental/taxi booths.

The walk over to the International terminal is doable and would take max 5 min.

http://local.google.com/maps?q=ccu+a...15000&t=h&z=18

S2 and 9W are pretty much the same airline, so I presume they will take of luggage, but this is Kolkata, so I would wait at the belt to see if your luggage doesn't appear. You have plenty of time after all

The international terminal really has nothing to speak of. The restaurant is basic and dark. The clipper lounge operated by oberoi is by invite only. The few decent rooms IAAI used to rent out there have been closed down when I checked earlier this year. They have a few rows of seats between the main hall and the place where the arriving pax come out of immigration where you could stretch out.