Dh is looking for a job in the US, but noone wants to hire right now, since we don't even know when we'll be moving. Understandable. So, we thought we'd have to wait until he got his visa and then really look for a job. Can he travel down for an interview even while he has his visa, without moving there yet? How does that work?

Yes, he can go back and forth after he's got his visa.

ya, the cr-1 or ir-1 is multiple entry!

So, to enter the first time, would I have to go before him? Or could he just travel down for an interview while I stayed here with the kids?

When he enters the first time he would "activate" the visa and get that paperwork rolling (SSN,if ya checked off the box.) I assume you have an addy in the USA where everything is being mailed to(SSn, greencard)??? He can go alone.