They are like any pet, the more you put in, the more you get out. If you take the time to tame your birds and spend time talking to them and generaly getting to know them, letting them have free flying time indoors (with care taken to close all doors/windows etc and dangers removed), then you will get birds who enjoy your company and are happy playful creatures. They are nice birds which make delightful pets, they spend a lot of time singing, as for talking they aren't one of the more vocal (only when it comes to human speech- bird talk they do very often and well) they often learn hello, however budgies don't have very clear voices when speaking human so don't expect too much from them.
Cockatiels are slightly more intelligent and so can learn more speech, they are very affectionate and as long as they are well hand tamed will often snuggle into you while sitting on your shoulder. Although tiels need a bigger cage and are slightly louder when singing.