Adding iphone registered to broken laptop onto laptop has another itunes account

Hello

My iphone is registered to my laptop which is completely broken so I cannot access my itunes account. I understand that I can download software which will allow me to transfer all the data from my itunes onto a new laptop but can I do this on a laptop that already has an itunes account on it (ie my husband's) or will all his stuff be erased when I download the software onto his laptop and try and add my iphone?

Thanks so much if you can help.

Lucy