As you will be far from home, Kolkata seems better.
1.Living conditions are better here, better climate, and if you don,t consider buying a car there is a lot better transportation system, like subway metro, tram, taxis, ferri, and the airport is also better connected to all part of the city, even there's the new AC bus system. Bangalore lacks the fast metro system, and having a 2 wheeler, or a four wheeler is a must, and traffic is also very bad here.
WINNER: KOLKATA
2. Education is good in both the cities, but Calcutta is more kid friendly, with science cities, planetarium, and lots of parks, but as for education only, both are one of the best.
WINNER: DRAW
3.living expenditure is lot less in kolkata, with wide variety of food stuffs, and from low to high range living system, and of course the transport is also a lot cheaper. whreas bangalore is very costly
WINNER: KOLKATA.
4.In cultural side, Kolkata takes a major victory, kolkata is rich in heritage, with lots and lots of temples, dramas, tollywood, etc.
WINNER:KOLKATA
5. In terms of security, Bangalore is a little better, but anyways they are pretty influenced by the politics.
WINNER:BANGALORE.
OVERALL
BANGALORE:2/5
KOLKATA; 4/5