Do you think this a good start on a story? Long but still...?

Well, you go from past tense to present tense a few times, so fix that. And "sled into the car" should be "slid into the car" I think. And saying 'hi' to greet some one isnt all that weird. And try not to use so many exclamation points, because if you use them a lot they lose their emphasis. But overall, I think it's pretty good.