If it is a quam tuner you should be able to get the locals but most likely the others will be encrypted and not viewable unless you have a cablecard (some digital sets have them most do not) and here they are $3 a month extra.
no because all channels are digital now. so whatever your tv tunes to is what its gonna get without a box. have you auto programed your tv? i would recommend getting a box and not a cable card so you can choose what channels you want and also have the option get two way communication which includes video on demand and stuff like that. then you dont have to deal with the hassles of pairing the card.