Milan (Milano) Linate is less than 10kms from the city centre, so that would be my choice, but a lot of the cheaper flights go to Malpensa which is approx 50kms from the city centre, but served now by a fast train. As to hotels etc, i'm out of the loop, but if you can hold off until the end of the month/august, then the choice will be large, the city empty, as the natives will be gone to the beach. Have fun!
SHJ