The people are technically still alive, with the question being largely whether or not they can be unfrozen while still being alive. The legal declaration of life - that the heart is still beating - is obviously not true in this case, but the retention of cells and brain structure are more important factors.
I do not think that patients who are preserved through cryonics are still alive while they are in storage. I do think that their vital organs and parts are kept in a state of preservations though, but there is no way to bring them back to life after they've gone through the process.
You hear news stories about someone being in icy water for 20 minutes and doctors being able revive the person. I think that's possible because the person's body temperature was lowered for minutes only. Patients preserved through cryonics have basically been frozen for an extended period of time. I believe these people are no longer alive and in spite of being frozen, cell deterioration still occurs.
They are just trying to preserve various body parts. They do not have know how to freeze people and keep them alive or bring them back alive. I think it is more they are trying to study how they could bring people back to life or preserve the living until a later date.
No, an individual who has undergone cryogenic preservation is not legally considered alive, at least not by the standards of life in the Commonwealth of Kentucky. Technically, in order for an individual to be determined to be dead, they must have no respiratory efforts and no heartbeat or electrical heart activity for a period of five minutes in three or more electrocardiograph leads. If one is "frozen" in a state of respiratory and cardiac arrest, they are not alive.