The answers to most of your questions will be influenced by what type of visa you will be able to get to stay here.
I am sure a desire to settle here won't be enough, you either need a family based visa or an employment/student based visa and that will determine how you get here, how long you stay and so on.
There are tons of people on here that have a lot of experience with all of this, so I will leave it til one pops in-I just wanted to give an initial response.
Also, your wife's particular skills would probably be in great demand here, there is often a great deal of demand for speech/language professionals in the health services (both public & private).
A law degree is pretty transferable into other areas, so you will always be employed, but I don't know that it will be enough on it's own to secure an employment based visa here, unless you specialise in some way.
Good Luck!