I stayed at the Candlewood (halfway between Newport and Exchange Place) a few weeks ago and liked it. But (especially with two small children) it was a bit of a walk to either station.

With that said, the hotel does operate a regular shuttle van to/from both stations. It's also adjacent to the Harborside light rail station, and the light rail will take you to either PATH station, though it's probably quicker to walk.

And I wish I'd known about the ten-ride-for-$15 PATH deal -- we'd have taken that in a heartbeat. I just loaded up a MetroCard and paid.