The white one looks like a Pekin to me. Unless it has red bumps (caruncles) above his beak, then it would be a Muscovy. The pic looks like he moved his bill while you were taking the pic, so it's one or the other.
The two smaller ones look like they could also be Mallards or as Amiga suggested, Rouens. Won't know for sure til they are fully grown. Very large, fat duck would be a Rouen.
Most of my ducks started laying when they were about a year old, so I wouldn't expect eggs til sometime next spring / early summer.