i'm wondering WHY you chose zurrieq or zejtun. well buses are frqeuent in both areas so that would be one good point for both to travel around, if u will not have a hired car. zurrieq offers the blue grotto which is a lovely place, one of the most beautiful in malta. u can go by walk, though it is a rather long walk. the centre is not lovely but asi said the blue grotto compensates all, though politically it is under the qrendi local council
parking should not be much of an issue especially in zurrieq. plane levels, well u r near the airport but not an extreemly strong nuisance as you are not exactly next door.
being from malta, would i have to hire an apartment as a foreginer however, i would not choose these two villages.