Hi Susan-
We had our DS in pullups (the cars design) for a few months, then last week, I decided we needed to start potty training, he had been peeing in the potty occasionally in the morning.
Our first day was not good, like you we had a lot of accidents, and we had a lot of laundry to do! But i had bought Cars underwear, thinking that might help him decide he wanted to do it.
After our first day, we bought a bunch of Hanes underwear, the next day was better, and about a week, ten days later, things are much easier. I haven't done the rewards system at all, and he seems to like that he stays dry, and that seems to be all he needs as a reward.
If he doesn't show interest, I wouldn't push it. We have the little potty in the kitchen, and fortunately a lot of bathrooms in the house.
Maybe try finding a book about potty training if he is into books?
If I had tried earlier, it probably wouldn't have worked.
Big hugs, Mama!