How long do you intend to visit for?
As a rough plan from Dublin you could stop at this waterpark, bit of fun after the journey
http://www.funtasia.ie/waterpark/home.aspx?AcceptsCookies=1
Then its around a 1.5 hr drive to the Mourne mountains where you could stop for a few days (beaches, mountains, hiking, biking etc)
http://www.discovernorthernireland.com/mournes/
From here you could visit Belfast if you wished or start the A2 Antrim Coast Road
http://www.causewaycoastandglens.com/portals/2/downloads/ccg_map.pdf
On this notable stops would be Carrickfergus Castle
http://www.discovernorthernireland.com/Carrickfergus-Castle-Carrickfergus-P2814
Carnfunnock Caravan Park is great for kids
http://www.carnfunnock.co.uk/
Then Giants Causeway, Carrick – a – reade Rope Bridge, Dunluce Castle etc.
You could stay a few days in Portrush or Portstewart for beaches and more traditional seaside stuff. Blairs is a good caravan park
http://www.blairscaravans.com/
After this you could go on to Derry or Donegal, possibly Glenveagh National Park.
http://www.glenveaghnationalpark.ie/
If you have any questions let me know.