iTunes help and/or (lost) password protected laptop

[Chopchopbusybusy]

DH is the admin on DD2s laptop. To do some things he needs to use his password, which he's forgotten. He's being a complete knob and doesn't seem to get that this is a pain in the arse (but that's probably a thread in relationships!)
So, she has a new iPhone and I think she needs to download latest version of iTunes to set it up, but we can't do that without knob's password. There must be a way to find out what the password is. Please? I've tried all variations of what he thought it might be.
Or, is there any other way. Can she open her iTunes on the family desktop? She has a seperate log on to the desktop and both knob and I have our own iTunes on there on seperate log ins.
I'm really not very techy so words with very few syllables would help me.

[CajaDeLaMemoria]

Does she know her iTunes password?

If she does, get her to log on to the family computer and she'll be able to use that.

As for the password, there are ways, but they can be complicated. It's generally much easier to format the whole laptop and reinstall (without letting your DH near it, ideally :P)

[Chopchopbusybusy]

Yes, she does know her iTunes password. I wasn't sure that she could just open it up on any computer. I did read something on line but they lost me with the explanation and it didn't look as straightforward as just signing in.
Sadly, he'll have to do it as I don't have a clue, although I'm tempted to get someone to do it for me and not tell him the password!