Sorry to hear about the accident, especially because of how it happened.
Gather your information so you know where you stand and be prepared to send it to the insurance company to verify what they should pay.
Be firm and businesslike with them, but don't let them BS you. If they say well, it's an old car...counter with so what, you oughta be glad it wasn't a new Benz! Remind them that it was the other driver's reckless actions that caused the damage, it wasn't just a little bump, it pushed the pickup truck into you HARD, look at that picture. Did that woman think she was at a demolition derby? And oh yeah, how are they going to compensate you for your time wasted because of THE other driver. Tell them they can get the money easily by RAISING the other driver's premium.
You got rear ended....did you have a doctor check yourself and your child out? Wait for a few days to see if anything turns up before saying you're fine.
In short, be nice and firm, and know what you want. Don't be afraid to fight for it, they count on people giving up easily and when you don't, they are much more likely to give you what you want if it's fair to get the case closed. Don't be afraid to be a dick to get fair compensation, it's your right.
Good luck,
vince