When the disability is mobility related:
Problems lifting/changing baby
Problems carrying baby or pushing a pushchair
How to manage a baby with one hand if you walk with a stick
Cooking can be dangerous around a baby too as if you are severely disabled (as defined by the DWP) you will not be able to cook a meal alone/unsupervised safely.
What care needs does the disabled parent have? This'll also be a factor.
I'm helping somebody fill in a DLA application at the moment, and the info is like 24 A4 pages of solid writing, just to describe how they do day to day activities. (I'd offer to send it to you, but it's not mind so I really can't).
If you don't actually have a set of questions or need actual statistics or anything, I would suggest, get a walking stick/crutches/or a pc chair with wheels/strap up an arm/blindfold yourself or something, get a doll and picture what how you would do things like changing a nappy etc.
To be honest, that'll probably be easier for your than getting an exact step by step description of those taks. If you don't have an idea, it's really hard for sometbody with a disability to explain exactly how they do things in a way you will be able to visualise.
Your uni might be able to help you by letting you see old study needs agreements with the names deleted or something. Maybe download a DLA application form so you know what kind of problems a disabled person might have day to day.
Hope this helps